core: fix VC++ warning C4703

This commit fixes VC++ warning C4703 in core/remote_access.cpp
"potentially uninitialized local pointer variable".

renderdoc/core/remote_access.cpp

@@ -244,7 +244,7 @@ void RenderDoc::RemoteAccessServerThread(void *s)
 		// receive handshake from client and get its name
 		{
 			PacketType type;
-			Serialiser *ser;
+			Serialiser *ser = NULL;
 			if(!RecvPacket(client, type, &ser))
 			{
 				SAFE_DELETE(ser);