FS-6531: #resolve set to tag on uuid_phone_event notify to make grandstream…

FS-6531: #resolve set to tag on uuid_phone_event notify to make grandstream happy, even tho they could have matched the dialog fine off the from tag like every other phone does.

src/mod/endpoints/mod_sofia/mod_sofia.c

@@ -1471,6 +1471,7 @@ static switch_status_t sofia_receive_message(switch_core_session_t *session, swi
 	case SWITCH_MESSAGE_INDICATE_PHONE_EVENT:
 		{
 			const char *event = "talk";
+			const char *full_to = NULL;
 
 			if (!zstr(msg->string_arg) && strcasecmp(msg->string_arg, event)) {
 				if (!strcasecmp(msg->string_arg, "hold")) {
@@ -1484,7 +1485,9 @@ static switch_status_t sofia_receive_message(switch_core_session_t *session, swi
 				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR,
 								  "Operation not permitted on an inbound non-answered call leg!\n");
 			} else {
-				nua_notify(tech_pvt->nh, NUTAG_NEWSUB(1), NUTAG_SUBSTATE(nua_substate_active), SIPTAG_SUBSCRIPTION_STATE_STR("active"),
+				full_to = switch_str_nil(switch_channel_get_variable(channel, "sip_full_to"));				
+				nua_notify(tech_pvt->nh, NUTAG_NEWSUB(1), NUTAG_SUBSTATE(nua_substate_active),
+						   TAG_IF((full_to), SIPTAG_TO_STR(full_to)),SIPTAG_SUBSCRIPTION_STATE_STR("active"),
 						   SIPTAG_EVENT_STR(event), TAG_END());
 			}