MT#56190 Adjust init scripts for shellcheck v0.9.0

Fix SC2086 issues ("Double quote to prevent globbing and word splitting", see
https://www.shellcheck.net/wiki/SC2086) in debian/ngcp-rtpengine-daemon.init
and debian/ngcp-rtpengine-recording-daemon.init, as reported by new shellcheck
version 0.9.0 (see https://github.com/koalaman/shellcheck/blob/master/CHANGELOG.md).

Change-Id: I97fe61d70dfddc420b8d0a7a9299a63b7a3061d7

debian/ngcp-rtpengine-daemon.init

@@ -92,7 +92,7 @@ case "$1" in
   stop)
 	log_daemon_msg "Stopping $DESC" "$NAME"
 	RC=0
-	start-stop-daemon --oknodo --stop --quiet --pidfile $PIDFILE \
+	start-stop-daemon --oknodo --stop --quiet --pidfile "$PIDFILE" \
 		--retry 5 --exec "$DAEMON" || RC=$?
 	if [ "$RC" -eq 0 ]; then
 	  ngcp-rtpengine-iptables-setup stop || true

debian/ngcp-rtpengine-recording-daemon.init

@@ -90,7 +90,7 @@ case "$1" in
   stop)
 	log_daemon_msg "Stopping $DESC" "$NAME"
 	RC=0
-	start-stop-daemon --oknodo --stop --quiet --pidfile $PIDFILE \
+	start-stop-daemon --oknodo --stop --quiet --pidfile "$PIDFILE" \
 		--retry 5 --exec "$DAEMON" || RC=$?
 	rm -f "$PIDFILE"
 	log_end_msg "$RC"