fix(linux): Fix headers and whitespace in AM62D performance rst

The performance guides use incorrect header hierarchy, fix
header hierarchy and whitespace to establish an easier to
read/parse html.

Signed-off-by: Judith Mendez <jm@ti.com>

Author: jmenti

source/devices/AM62DX/linux/Linux_Performance_Guide.rst

@@ -1,10 +1,11 @@
 
-====================================
+#################################
  Linux 12.00.00 Performance Guide
-====================================
+#################################
 
-.. rubric::  **Read This First**
-   :name: read-this-first-kernel-perf-guide
+***************
+Read This First
+***************
 
 **All performance numbers provided in this document are gathered using
 following Evaluation Modules unless otherwise specified.**
@@ -18,26 +19,30 @@ following Evaluation Modules unless otherwise specified.**
 
 Table:  Evaluation Modules
 
-.. rubric::  About This Manual
-   :name: about-this-manual-kernel-perf-guide
+*****************
+About This Manual
+*****************
 
 This document provides performance data for each of the device drivers
 which are part of the Processor SDK Linux package. This document should be
 used in conjunction with release notes and user guides provided with the
 Processor SDK Linux package for information on specific issues present
 with drivers included in a particular release.
 
-.. rubric::  If You Need Assistance
-   :name: if-you-need-assistance-kernel-perf-guide
-
 For further information or to report any problems, contact
 https://e2e.ti.com/ or https://support.ti.com/
 
+|
+
+*****************
 System Benchmarks
------------------
+*****************
+
+|
 
 LMBench
-^^^^^^^
+=======
+
 LMBench is a collection of microbenchmarks of which the memory bandwidth 
 and latency related ones are typically used to estimate processor 
 memory system performance. More information about lmbench at
@@ -181,7 +186,8 @@ Execute the LMBench with the following:
     "tcp_latency_using_localhost (microsec)","0.89 (min 0.76, max 1.02)"
 
 Dhrystone
-^^^^^^^^^
+=========
+
 Dhrystone is a core only benchmark that runs from warm L1 caches in all
 modern processors. It scales linearly with clock speed.
 
@@ -203,7 +209,8 @@ Execute the benchmark with the following:
     "dhrystone_per_second (dhrystonep)","6789289.58 (min 6451613.00, max 7142857.00)"
 
 Whetstone
-^^^^^^^^^
+=========
+
 Whetstone is a benchmark primarily measuring floating-point arithmetic performance.
 
 Execute the benchmark with the following:
@@ -218,7 +225,8 @@ Execute the benchmark with the following:
     "whetstone (mips)","5833.33 (min 5000.00, max 10000.00)"
 
 Linpack
-^^^^^^^
+=======
+
 Linpack measures peak double precision (64 bit) floating point performance in
 solving a dense linear system.
 
@@ -228,7 +236,8 @@ solving a dense linear system.
     "linpack (kflops)","580360.75 (min 579515.00, max 581724.00)"
 
 Stream
-^^^^^^
+======
+
 STREAM is a microbenchmark for measuring data memory system performance without
 any data reuse. It is designed to miss on caches and exercise data prefetcher
 and speculative accesses.
@@ -254,7 +263,8 @@ Execute the benchmark with the following:
     "triad (mb/s)","2384.27 (min 2377.90, max 2393.60)"
 
 CoreMarkPro
-^^^^^^^^^^^
+===========
+
 CoreMark®-Pro is a comprehensive, advanced processor benchmark that works with
 and enhances the market-proven industry-standard EEMBC CoreMark® benchmark.
 While CoreMark stresses the CPU pipeline, CoreMark-Pro tests the entire processor,
@@ -291,7 +301,8 @@ and floating-point workloads, and data sets for utilizing larger memory subsyste
     "zip-test (workloads/)","78.74 (min 74.07, max 83.33)"
 
 MultiBench
-^^^^^^^^^^
+==========
+
 MultiBench™ is a suite of benchmarks that allows processor and system designers to
 analyze, test, and improve multicore processors. It uses three forms of concurrency:
 Data decomposition: multiple threads cooperating on achieving a unified goal and
@@ -338,11 +349,13 @@ thread-enabled workloads to be tested.
     "x264-4mq (workloads/)","0.58"
     "x264-4mqw1 (workloads/)","0.58"
 
+|
+
 Boot-time Measurement
----------------------
+=====================
 
 Boot media: MMCSD
-^^^^^^^^^^^^^^^^^
+-----------------
 
 .. csv-table:: Linux boot time MMCSD
     :header: "Boot Configuration","am62dxx_evm-fs: Boot time in seconds: avg(min,max)"
@@ -354,7 +367,8 @@ Boot time numbers [avg, min, max] are measured from "Starting kernel" to Linux p
 |
 
 Ethernet
---------
+========
+
 Ethernet performance benchmarks were measured using :command:`netperf` 2.7.1 https://hewlettpackard.github.io/netperf/doc/netperf.html
 Test procedures were modeled after those defined in RFC-2544:
 https://tools.ietf.org/html/rfc2544, where the DUT is the TI device
@@ -420,11 +434,11 @@ Running the following commands will trigger :command:`netperf` clients to measur
    netperf -H <DUT ip> -j -C -l 60 -t UDP_STREAM -b <burst_size> -w <wait_time> -- -m <UDP datagram size>
       -k DIRECTION,THROUGHPUT,MEAN_LATENCY,LOCAL_CPU_UTIL,REMOTE_CPU_UTIL,LOCAL_BYTES_SENT,REMOTE_BYTES_RECVD,LOCAL_SEND_SIZE
 
-CPSW/CPSW2g/CPSW3g Ethernet Driver
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+CPSW/CPSW2g/CPSW3g Ethernet
+---------------------------
 
-.. rubric::  UDP Throughput
-   :name: CPSW2g-udp-throughput-0-loss
+UDP Throughput
+^^^^^^^^^^^^^^
 
 .. csv-table:: CPSW2g UDP Egress Throughput 0 loss
     :header: "Frame Size(bytes)","am62dxx_evm-fs: UDP Datagram Size(bytes) (LOCAL_SEND_SIZE)","am62dxx_evm-fs: THROUGHPUT (Mbits/sec)","am62dxx_evm-fs: Packets Per Second (kPPS)","am62dxx_evm-fs: CPU Load % (LOCAL_CPU_UTIL)"
@@ -452,11 +466,11 @@ CPSW/CPSW2g/CPSW3g Ethernet Driver
 
 |
 
-USB Driver
-----------
+USB
+===
 
 USB Device Controller
-^^^^^^^^^^^^^^^^^^^^^
+---------------------
 
 .. csv-table:: USBDEVICE HIGHSPEED SLAVE_READ_THROUGHPUT
     :header: "Number of Blocks","am62dxx_evm-fs: Throughput (MB/sec)"
@@ -470,11 +484,11 @@ USB Device Controller
 
 |
 
-CRYPTO Driver
--------------
+CRYPTO
+======
 
 OpenSSL Performance
-^^^^^^^^^^^^^^^^^^^
+-------------------
 
 .. csv-table:: OpenSSL Performance
     :header: "Algorithm","Buffer Size (in bytes)","am62dxx_evm-fs: throughput (KBytes/Sec)"
@@ -546,3 +560,5 @@ Listed for each algorithm are the code snippets used to run each
 ::
 
     time -v openssl speed -elapsed -evp aes-128-cbc
+
+|