rc-cgroup.sh: Do not add leading spaces to cgroup values

We were starting the value we write to the cgroup setting file with
leading spaces and this was causing issues. This change makes sure that
we aren't adding leading spaces to the value.

X-Gentoo-Bug: 562354
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=562354

sh/rc-cgroup.sh.in

@@ -54,7 +54,9 @@ cgroup_set_values()
 				val=
 				;;
 			*)
-				val="$val $1"
+				[ -n "$val" ] &&
+					val="$val $1" ||
+					val="$1"
 				;;
 		esac
 		shift