mcastmngr: fix multicast forwarding on untagged interface.

Modifying the lookup method for forwarding multicast packets enables
forwarding on both tagged and untagged upstream interfaces.

I have tested:
- forwarding of traffic in untagged interface.
- forwarding of traffic on tagged interface.
- response to queries in above scenarios by upstream server.
- forwarding of unsolicited joins and leaves to upstream server.

I cannot see a fault at the moment

mcastmngr/files/etc/init.d/mcast

@@ -9,6 +9,7 @@ NAME=mcast
 include /lib/network
 include /lib/mcast
 
+
 service_triggers() {
 	procd_add_reload_trigger network $NAME
 }
@@ -24,6 +25,11 @@ start_service() {
 	procd_close_instance
 }
 
+boot() {
+	setup_mcast_mode
+	start
+}
+
 stop_service() {
 	service_stop $PROG_EXE
 }

mcastmngr/files/lib/mcast/broadcom.sh

@@ -395,6 +395,11 @@ config_global_params() {
 	echo $mldv2_unsolicited_report_interval > /proc/sys/net/ipv6/conf/all/mldv2_unsolicited_report_interval
 }
 
+setup_mcast_mode() {
+	# set the mode at chip to allow both tagged and untagged multicast forwarding
+	bs /b/c iptv lookup_method=group_ip_src_ip
+}
+
 configure_mcast() {
 	rm -f $CONFFILE
 	touch $CONFFILE