Added verification if masking of initctl already exists

This fixes tdm instalation on Ubuntu in chroot

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>
(cherry picked from commit e5f2386a78)

ubuntu/maverick/tdebase/debian/tdm-trinity.postinst

@@ -142,8 +142,9 @@ case "$1" in
 esac
 
 # Upstart is not active?
+UPSTART_DIVERT=`dpkg-divert --listpackage /sbin/initctl`
 UPSTART_ACTIVE=`dbus-send --system --print-reply --dest=com.ubuntu.Upstart /com/ubuntu/Upstart org.freedesktop.DBus.Properties.Get string:com.ubuntu.Upstart0_6 string:version 2>/dev/null || true`
-if [ -z "$UPSTART_ACTIVE" ]; then
+if [ -z "$UPSTART_DIVERT" ] && [ -z "$UPSTART_ACTIVE" ]; then
   echo "Upstart is not active - masking initctl" >&2
   dpkg-divert --local --rename --add /sbin/initctl
   ln -s /bin/true /sbin/initctl
@@ -152,7 +153,7 @@ fi
 #DEBHELPER#
 
 # Upstart is not active?
-if [ -z "$UPSTART_ACTIVE" ]; then
+if [ -z "$UPSTART_DIVERT" ] && [ -z "$UPSTART_ACTIVE" ]; then
   rm /sbin/initctl
   dpkg-divert --local --rename --remove /sbin/initctl
 fi