Implement QStandardPaths::GenericConfigLocation for WinRT.

Same logic for locaton used as in other Windows variants.

Change-Id: I5f71710d28ea1338748c9bd41d48bba15e674baa
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>

src/corelib/io/qstandardpaths_winrt.cpp

@@ -74,6 +74,7 @@ QString QStandardPaths::writableLocation(StandardLocation type)
 
     switch (type) {
     case ConfigLocation: // same as DataLocation, on Windows
+    case GenericConfigLocation: // same as GenericDataLocation, on Windows
     case DataLocation:
     case GenericDataLocation: {
         ComPtr<IApplicationDataStatics> applicationDataStatics;