tools headers: Import iosubmit_cmds512()

tools headers: Import iosubmit_cmds512()

Import iosubmit_cmds512() from arch/x86/include/asm/io.h into tools/ so
it can be used by VFIO selftests to interact with Intel DSA devices.

Also pull in movdir64b() from arch/x86/include/asm/special_insns.h into
tools/, which is the underlying instruction used by iosubmit_cmds512().

Changes made when importing: None

Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-21-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>