intel/gm45: Use MMCONF_SUPPORT_DEFAULT

Change all PCI configuration accesses to MMIO for all boards
with gm45 chipset. To enable MMIO style access, add explicit
PCI IO config write in the bootblock.

Change-Id: Id1c839b7d669946e0ca8b6837e5152ebcb9cd334
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/3600
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>
diff --git a/src/northbridge/intel/gm45/Kconfig b/src/northbridge/intel/gm45/Kconfig
index 16a0bf1..adf1c1b 100644
--- a/src/northbridge/intel/gm45/Kconfig
+++ b/src/northbridge/intel/gm45/Kconfig
@@ -29,4 +29,8 @@
 	select MMCONF_SUPPORT_DEFAULT
 	select IOMMU
 
+config BOOTBLOCK_NORTHBRIDGE_INIT
+	string
+	default "northbridge/intel/gm45/bootblock.c"
+
 endif