net: shell: events: IPv4 mcast join and leave were missing

The event monitor did not handled IPv4 multicast join/leave
event information.

Signed-off-by: Jukka Rissanen <[email protected]>

Author: jukkar

subsys/net/lib/shell/events.c

@@ -334,6 +334,18 @@ static char *get_l3_desc(struct event_msg *msg,
 		*desc = "DHCPv4";
 		*desc2 = "stop";
 		break;
+	case NET_EVENT_IPV4_MCAST_JOIN:
+		*desc = "IPv4 mcast";
+		*desc2 = "join";
+		info = net_addr_ntop(AF_INET, msg->data, extra_info,
+				     extra_info_len);
+		break;
+	case NET_EVENT_IPV4_MCAST_LEAVE:
+		*desc = "IPv4 mcast";
+		*desc2 = "leave";
+		info = net_addr_ntop(AF_INET, msg->data, extra_info,
+				     extra_info_len);
+		break;
 	case NET_EVENT_IPV4_ACD_SUCCEED:
 		*desc = "IPv4 ACD";
 		*desc2 = "ok";