merge coreboot/u-boot download logic to one script

they are fundamentally the same, in an lbmk context.

they are downloaded in the same way, and compiled in
the same way!

(Kconfig infrastructure, board-specific code, the way
submodules are used in git, etc)

~200 sloc reduction in resources/scripts

the audit begins

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

resources/scripts/build/release/roms

@@ -24,14 +24,14 @@ set -u -e
 projectname="$(cat projectname)"
 version="version-unknown"
 versiondate="version-date-unknown"
-cbtree="default"
+tree="default"
 target=""
 CONFIG_HAVE_MRC=""
 CONFIG_HAVE_ME_BIN=""
 CONFIG_KBC1126_FIRMWARE=""
 CONFIG_INCLUDE_SMSC_SCH5545_EC_FW=""
-ifdtool="cbutils/${cbtree}/ifdtool"
-cbfstool="cbutils/${cbtree}/cbfstool"
+ifdtool="cbutils/${tree}/ifdtool"
+cbfstool="cbutils/${tree}/cbfstool"
 
 main()
 {
@@ -118,10 +118,10 @@ strip_archive()
 {
 	romdir=${1}
 
-	if [ ! -d coreboot/${cbtree} ]; then
-		./download coreboot ${cbtree} || exit 1
+	if [ ! -d coreboot/${tree} ]; then
+		./fetch_trees coreboot ${tree} || exit 1
 	fi
-	./build module cbutils ${cbtree} || exit 1
+	./build module cbutils ${tree} || exit 1
 
 	rm -Rf "${romdir}_tmp" # dirty hack, to reduce disk io later
 	# rather than using /tmp, which might not be tmpfs