x86, mrst: Add Kconfig dependencies for Moorestown

The Moorestown platform requires IOAPIC for all interrupts from the
south complex, since there is no legacy PIC.

Furthermore, Moorestown I/O requires PCI.  Moorestown PCI depends on PCI MMCONFIG
and DIRECT method to perform device enumeration, as there is no PCI BIOS.

[ hpa: rewrote commit message ]

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
LKML-Reference: <1267120934-9505-1-git-send-email-jacob.jun.pan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>