Bitfields for Intel 82379AB/82371 APIC Base Address Relocation:
Bit(s)	Description	)
 7	reserved
 6	(82379AB) reserved
 6	(82371) A12 mask
	=1 ignore address bit 12 in APIC address
 5-0	bits 15-10 of APIC memory address (ORed with FEC00000h to form base
	  address)
SeeAlso: #01064,#01167,#01077,MEM FEC00000h