Add windows definitions to make the code model happy.

__stdcall for all compilers (MSVC and MinGW, possibly others may use it)
__w64 is MSVC only, deprecated there, but still used in some places

Reviewed-By: Roberto Raggi

src/plugins/cpptools/cppmodelmanager.cpp

@@ -150,6 +150,7 @@ static const char pp_configuration[] =
 
     // ### add macros for win32
     "#define __cdecl\n"
+    "#define __stdcall\n"
     "#define QT_WA(x) x\n"
     "#define API\n"
     "#define WINAPI\n"

src/plugins/projectexplorer/toolchain.cpp

@@ -346,6 +346,7 @@ QByteArray MSVCToolChain::predefinedMacros()
 {
     if (m_predefinedMacros.isEmpty()) {
         m_predefinedMacros += "#define __MSVCRT__\n"
+                              "#define __w64\n"
                               "#define __int64 long long\n"
                               "#define __int32 long\n"
                               "#define __int16 short\n"