Add SPI flash driver

This driver is taken from u-boot and adapted to match
coreboot. It still contains some hacks and is ICH specific
at places.

Change-Id: I97dd8096f7db3b62f8f4f4e4d08bdee10d88f689
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/997
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
diff --git a/src/southbridge/intel/bd82x6x/Makefile.inc b/src/southbridge/intel/bd82x6x/Makefile.inc
index 5732254..f086426 100644
--- a/src/southbridge/intel/bd82x6x/Makefile.inc
+++ b/src/southbridge/intel/bd82x6x/Makefile.inc
@@ -34,6 +34,8 @@
 ramstage-y += reset.c
 ramstage-y += watchdog.c
 
+ramstage-y += spi.c
+
 ramstage-$(CONFIG_HAVE_SMI_HANDLER) += smi.c
 smm-$(CONFIG_HAVE_SMI_HANDLER) += smihandler.c $(me-src-y) finalize.c