Fix multicast double free issue in IPv4.

- IPv4 had the same problem as v6. Most likely this was an oversight
  when converting from a C to a C++ module. Might help with #6736 and
  #8894.

src/add-ons/kernel/network/protocols/ipv4/ipv4.cpp

@@ -163,10 +163,16 @@ struct MulticastStateHash {
 struct ipv4_protocol : net_protocol {
 	ipv4_protocol()
 		:
+		raw(NULL),
 		multicast_filter(this)
 	{
 	}
 
+	~ipv4_protocol()
+	{
+		delete raw;
+	}
+
 	RawSocket*			raw;
 	uint8				service_type;
 	uint8				time_to_live;
@@ -1029,9 +1035,8 @@ ipv4_uninit_protocol(net_protocol* _protocol)
 {
 	ipv4_protocol* protocol = (ipv4_protocol*)_protocol;
 
-	delete protocol->raw;
-	delete protocol->multicast_address;
 	delete protocol;
+
 	return B_OK;
 }
 

src/add-ons/kernel/network/protocols/ipv6/ipv6.cpp

@@ -180,6 +180,7 @@ struct MulticastStateHash {
 struct ipv6_protocol : net_protocol {
 	ipv6_protocol()
 		:
+		raw(NULL),
 		multicast_filter(this)
 	{
 	}