x86, pageattr: Correct WBINVD spelling in comment

It is WBINVD, for INValiDate and not "wbindv". Use caps for instruction
names, while at it.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1394633584-5509-4-git-send-email-bp@alien8.de


Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>