scripts/fetch: add missing die statement

Noticed this while the Yocto Project's git server was down for
maintenance.

scripts/fetch.sh

@@ -43,7 +43,8 @@ update_repo() {
 		if [ -z "${GIT_LOCAL_REF_DIR}" ]; then
 			git clone ${uri} ${path} || die "unable to clone ${uri}"
 		else
-			git clone --reference ${GIT_LOCAL_REF_DIR}/`basename ${path}` ${uri} ${path}
+			git clone --reference ${GIT_LOCAL_REF_DIR}/`basename ${path}` \
+                ${uri} ${path} || die "unable to clone ${uri}"
 		fi
 		pushd ${path} > /dev/null
 	fi