swclock: select a default reference file

If $RC_SVCDIR/shutdowntime does not exist, we need a default reference
file. It is safe to use @PREFIX@/sbin/runscript for this purpose.

Reported-By: Robin H. Johnson <robbat2@gentoo.org>
X-Gentoo-Bug: 376249
X-Gentoo-Bug-URL: http://bugs.gentoo.org/show_bug.cgi?id=376249

init.d/swclock.in

@@ -16,7 +16,9 @@ depend()
 start()
 {
 	ebegin "Setting the local clock based on last shutdown time"
-	swclock --warn
+	if ! swclock 2> /dev/null; then
+	swclock --warn @PREFIX@/sbin/runscript
+	fi
 	eend $?
 }