Fixed compilation on mingw.

src/ports/SkOSLibrary_win.cpp

 
 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkTypes.h"
 #if defined(SK_BUILD_FOR_WIN32)
 
 #include "SkOSLibrary.h"
 #include <windows.h>
 
 void* DynamicLoadLibrary(const char* libraryName) {
     return LoadLibraryA(libraryName);
 }
 
 void* GetProcedureAddress(void* library, const char* functionName) {
-    return ::GetProcAddress((HMODULE)library, functionName);
+    return (void*)::GetProcAddress((HMODULE)library, functionName);

[bungeman-skia, 2016/01/14 18:04:58]

Can we use a c++ cast here? Something like
reinterpret_cast<void*>(GetProcAddress(...)) or
*reinterpret_cast<void**>(GetProcAddress(...)).

 }
 
 #endif//defined(SK_BUILD_FOR_WIN32)