Move all IT87xx specific SPI routines from spi.c to a separate file it87spi.c

No behavioural changes, but greatly improved SPI abstraction.

Corresponding to flashrom svn r229 and coreboot v2 svn r3305.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Peter Stuge <peter@stuge.se>
diff --git a/Makefile b/Makefile
index 9ea7d73..2f0b290 100644
--- a/Makefile
+++ b/Makefile
@@ -24,7 +24,7 @@
 	sst28sf040.o am29f040b.o mx29f002.o sst39sf020.o m29f400bt.o \
 	w49f002u.o 82802ab.o msys_doc.o pm49fl004.o sst49lf040.o \
 	sst49lfxxxc.o sst_fwhub.o layout.o cbtable.o flashchips.o \
-	flashrom.o w39v080fa.o sharplhf00l04.o w29ee011.o spi.o
+	flashrom.o w39v080fa.o sharplhf00l04.o w29ee011.o spi.o it87spi.o
 
 all: pciutils dep $(PROGRAM)