doc/configuration: explicitly document drivers not expecting arguments

Signed-off-by: Bastian Krause <bst@pengutronix.de>

Author: Bastian-Krause

doc/configuration.rst

@@ -1537,6 +1537,9 @@ Binds to:
 Implements:
   - None (yet)
 
+Arguments:
+  - None
+
 ShellDriver
 ~~~~~~~~~~~
 A ShellDriver binds on top of a `ConsoleProtocol` and is designed to interact
@@ -2876,6 +2879,9 @@ Binds to:
 Implements:
   - :any:`VideoProtocol`
 
+Arguments:
+  - None
+
 Although the driver can be used from Python code by calling the `stream()`
 method, it is currently mainly useful for the ``video`` subcommand of
 ``labgrid-client``.