[XAM/Net] Added unified method of returning WSA error codes

src/xenia/kernel/xsocket.h

@@ -118,6 +118,8 @@ class XSocket : public XObject {
   int SendTo(uint8_t* buf, uint32_t buf_len, uint32_t flags, N_XSOCKADDR_IN* to,
              uint32_t to_len);
 
+  uint32_t GetLastWSAError() const;
+
   struct packet {
     // These values are in network byte order.
     xe::be<uint16_t> src_port;