[Chore] (buildsystem): fix compilation and linking on Windows when building 3rdparty from source

MobileGL/MG_Impl/EGLImpl/Temporary/TemporaryEGLImpl.cpp

@@ -102,7 +102,11 @@ namespace MobileGL {
 
         __eglMustCastToProperFunctionPointerType GetProcAddress(const char* name) {
             MGLOG_D("eglGetProcAddress(%s)", name);
+#ifndef WIN32
             void* proc = dlsym(RTLD_DEFAULT, (const char*)name);
+#else
+            void* proc = NULL;
+#endif
             if (!proc) {
                 MGLOG_W("Failed to get function: %s", (const char*)name);
                 return nullptr;