IPACM: Fix lan2lan RT rule failed issue

In customer cases, if one of the tethered interfaces
is not registered Tx/Rx properties in IPA-HW, the
LAN2LAN RT rule construction will add to wrong pipes
which causes the ipa crash. The fix is to add the
check when those lan2lan events are posting.

Change-Id: I3e1ea515914c55f3c2c9861ad62e227af2a3d814
diff --git a/ipacm/src/IPACM_Lan.cpp b/ipacm/src/IPACM_Lan.cpp
index 19c6950..dca47ed 100644
--- a/ipacm/src/IPACM_Lan.cpp
+++ b/ipacm/src/IPACM_Lan.cpp
@@ -2615,6 +2615,12 @@
 /*handle lan2lan client active*/
 int IPACM_Lan::handle_lan2lan_client_active(ipacm_event_data_all *data, ipa_cm_event_id event)
 {
+	if((tx_prop == NULL) || (rx_prop == NULL))
+	{
+		IPACMDBG_H("No tx/rx properties registered for iface %s, not posting lan2lan event(%d)\n", dev_name, event);
+		return IPACM_SUCCESS;
+	}
+
 	if(data == NULL)
 	{
 		IPACMERR("Event data is empty.\n");