Bitfields for Intel 82371MX I/O configuration address register:
Bit(s)	Description	)
 15-10	reserved
 9-1	I/O Configuration Address
 0	I/O Configuration Address Enabled
Note:	This register provides an I/O address range to be forwarded to the
	  Extended I/O Bus for accesses to the configuration space of an
	  integrated I/O device. PCI address bits 9-1 are compared to bits
	  9-1 of this register. Address bits 31-10 must be 0.
SeeAlso: #01168,PORT xxxxh"Intel 82371"