Add flag to control Winsocket initialization (#3060)

When WAMR is embedded to other application, the lifecycle of the socket
might conflict with other usecases. E.g. if WAMR is deinitialized before any
other use of sockets, the application goes into the invalid state. The new
flag allows host application to take control over the socket initialization.

core/shared/platform/windows/win_socket.c

@@ -32,6 +32,7 @@ static bool is_winsock_inited = false;
 int
 init_winsock()
 {
+#if WASM_ENABLE_HOST_SOCKET_INIT == 0
     WSADATA wsaData;
 
     if (!is_winsock_inited) {
@@ -42,6 +43,7 @@ init_winsock()
 
         is_winsock_inited = true;
     }
+#endif
 
     return BHT_OK;
 }
@@ -49,9 +51,11 @@ init_winsock()
 void
 deinit_winsock()
 {
+#if WASM_ENABLE_HOST_SOCKET_INIT == 0
     if (is_winsock_inited) {
         WSACleanup();
     }
+#endif
 }
 
 int