The ID register access was the only difference between them, so
after switching to the ArmHasGicSystemRegisters () helper, there
is no longer any need to have separate ARM/AArch64 source files
for ArmGicArchSecLib, so unify them and drop the subdirectories.
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Signed-off-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@arm.com>