x86/signal/64: Move 64-bit signal code to its own file

  [ bp: Fixup merge conflict caused by changes coming from the kbuild tree. ]

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/r/20220606203802.158958-9-brgerst@gmail.com
Signed-off-by: Borislav Petkov <bp@suse.de>

Author: Brian Gerst

arch/x86/kernel/Makefile

@@ -44,7 +44,7 @@ obj-y			+= head_$(BITS).o
 obj-y			+= head$(BITS).o
 obj-y			+= ebda.o
 obj-y			+= platform-quirks.o
-obj-y			+= process_$(BITS).o signal.o
+obj-y			+= process_$(BITS).o signal.o signal_$(BITS).o
 obj-$(CONFIG_COMPAT)	+= signal_compat.o
 obj-y			+= traps.o idt.o irq.o irq_$(BITS).o dumpstack_$(BITS).o
 obj-y			+= time.o ioport.o dumpstack.o nmi.o
@@ -53,7 +53,7 @@ obj-y			+= setup.o x86_init.o i8259.o irqinit.o
 obj-$(CONFIG_JUMP_LABEL)	+= jump_label.o
 obj-$(CONFIG_IRQ_WORK)  += irq_work.o
 obj-y			+= probe_roms.o
-obj-$(CONFIG_X86_32)	+= sys_ia32.o signal_32.o
+obj-$(CONFIG_X86_32)	+= sys_ia32.o
 obj-$(CONFIG_IA32_EMULATION)	+= sys_ia32.o signal_32.o
 obj-$(CONFIG_X86_64)	+= sys_x86_64.o
 obj-$(CONFIG_X86_ESPFIX64)	+= espfix_64.o