MFC r257858:
Fix signal delivery for the iBCS2 binaries.

Approved by:	re (gjb)
MFC r257856:
Add bits for the AMD features from CPUID function 0x80000001 ECX,
described in the rev. 3.0 of the Kabini BKDG, document 48751.pdf.

Approved by:	re (gjb)