handle/make/config: fix distclean/crossgcc-clean

these commands weren't being run at all, leading
to binaries (such as xgcc) not being removed, and
thus they were present in tested release archives.

this bug did not affect libreboot 20230625. it
appeared during my audit, post-20230625.

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

script/handle/make/config

@@ -106,8 +106,7 @@ main()
 
 handle_defconfig()
 {
-	handle_dependencies "${target}" || \
-	    fail "handle_defconfig: failed call to handle_dependencies"
+	handle_dependencies "${target}" || return 0
 
 	for y in "${target_dir}/config"/*; do
 		[ -f "${y}" ] || continue
@@ -150,7 +149,7 @@ handle_dependencies()
 		    [ "${mode}" = "crossgcc-clean" ]; then
 			printf "Directory %s doesn't exist; skipping clean\n" \
 			    "${codedir}" 1>&2
-			exit 0
+			return 1
 		fi
 		./update project trees "${project}" "${target}" || \
 		    fail "handle_dependencies: can't fetch ${project}/${target}"