ich9m mainboards: use pre-assembled ifd/gbe files

This cuts down on build time, and it will allow libreboot
to remove large chunks of code.

these ifd/gbe configs are just binary-encoded config files,
in a format well-understood. they can easily be opened up
and displayed, using ich9show or ifdtool, and manipulated
by these tools; bincfg can generate them from scratch, and
nvmutil can change mac addresses, for example.

so, do this and remove from lbmk the following:

* ich9utils (which contains ich9gen) - not needed anymore
* code in lbmk for handling ich9gen and insertions; the
  coreboot build system is now used, for this same purpose,
  so remove such code from lbmk

this results in a massive code size reduction (thousands of
lines) in lbmk; smaller when only looking at the build
system, but much larger when you consider that ich9utils
is also removed (about 3k sloc)

Signed-off-by: Leah Rowe <leah@libreboot.org>

script/build/release/src

@@ -162,7 +162,7 @@ purge_files()
 		    err "purge_files: ${p}: cannot clean the source trees"
 	done
 
-	for p in bios_extract flashrom grub ich9utils uefitool; do
+	for p in bios_extract flashrom grub uefitool; do
 		./handle make file -c "${p}" || \
 		    err "purge_files: !./handle make file -c ${p}"
 	done
@@ -170,7 +170,7 @@ purge_files()
 		./handle make file -c "memtest86plus/build${p}" || \
 		    err "purge_files: cannot clean memtest86+ build${p}"
 	done
-	for p in "nvmutil" "ich9utils" "spkmodem_recv" "e6400-flash-unlock"; do
+	for p in "nvmutil" "spkmodem_recv" "e6400-flash-unlock"; do
 		make clean -C "util/${p}" || \
 		    err "purge_files 2: !make clean -C ${util}/p"
 	done