x86, nop: Make the ASM_NOP* macros work from assembly

Make the ASM_NOP* macros work in actual assembly files.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1334794610-5546-2-git-send-email-hpa@zytor.com