fix build issue building coreboot utils

just run make directly. the trees script isn't really
designed to directly build directories, so don't.

nothing wrong with good old fashioned make -C

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

include/lib.sh

@@ -157,7 +157,7 @@ check_defconfig()
 handle_coreboot_utils()
 {
 	for util in cbfstool ifdtool; do
-		x_ ./update trees $_f "src/coreboot/$1/util/$util"
+		x_ make -C "src/coreboot/$1/util/$util"
 		[ -z "$mode" ] && [ ! -f "cbutils/$1/$util" ] && \
 			x_ mkdir -p "cbutils/$1" && \
 			x_ cp "src/coreboot/$1/util/$util/$util" "cbutils/$1"