remove redundant sync calls

The localmount and mount-ro scripts were flushing pending disk writes by
calling sync twice in succession. This is no longer necessary; see the
bug report and blog post for reasons we were still doing this.

Reported-by: Patrick Lauer <patrick@gentoo.org>
X-Gentoo-Bug: 487382
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=487382

init.d/localmount.in

@@ -59,7 +59,7 @@ stop()
 	no_umounts_r="^($no_umounts_r)$"
 
 	# Flush all pending disk writes now
-	sync; sync
+	sync
 
 	. "$RC_LIBEXECDIR"/sh/rc-mount.sh
 

init.d/mount-ro.in

@@ -15,7 +15,7 @@ start()
 	local ret=0
 
 	# Flush all pending disk writes now
-	sync; sync
+	sync
 
 	ebegin "Remounting remaining filesystems read-only"
 	# We need the do_unmount function