Fix server crash on info request with invalid token

Author: Robyt3

src/engine/server/server.cpp

@@ -1168,7 +1168,7 @@ void CServer::PumpNetwork()
 				CUnpacker Unpacker;
 				Unpacker.Reset((unsigned char*)Packet.m_pData+sizeof(SERVERBROWSE_GETINFO), Packet.m_DataSize-sizeof(SERVERBROWSE_GETINFO));
 				int SrvBrwsToken = Unpacker.GetInt();
-				if(Unpacker.Error())
+				if(Unpacker.Error() || SrvBrwsToken < 0)
 					continue;
 
 				CPacker Packer;