rom.sh: simplify ccache handling for coreboot

we simply do not need to run the make-oldconfig command
at all, and after removing it, the "cook" function seemed
quite redundant so i merged it with mkvendorfiles()

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

include/rom.sh

@@ -45,7 +45,8 @@ mkpayload_grub()
 
 mkvendorfiles()
 {
-	[ -z "$mode" ] && $dry cook_coreboot_config
+	[ -n "$mode" ] || [ ! -f "$srcdir/.config" ] || $dry printf \
+	    "CONFIG_CCACHE=y\n" >> "$srcdir/.config" || err "$srcdir: !cook"; :
 	fx_ check_coreboot_util printf "cbfstool\nifdtool\n"
 	printf "%s\n" "${version%%-*}" > "$srcdir/.coreboot-version" || \
 	    err "!mk $srcdir .coreboot-version"
@@ -53,14 +54,6 @@ mkvendorfiles()
 	    x_ ./mk download "$target"; :
 }
 
-cook_coreboot_config()
-{
-	[ -f "$srcdir/.config" ] || return 0
-	printf "CONFIG_CCACHE=y\n" >> "$srcdir/.config" || \
-	    err "$srcdir/.config: Could not enable ccache"
-	make -C "$srcdir" oldconfig || err "Could not cook $srcdir/.config"; :
-}
-
 check_coreboot_util()
 {
 	[ "$badhash" = "y" ] && x_ rm -f "elf/$1/$tree/$1"