Replace use of putenv in test case

This should be using qputenv; putenv is deprecated on MSVC.

Change-Id: I7c27cf5f7955624fa3553b7a34ab11c6fae462b8
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>
Fix QTimeZone test compilation on WinRT

WinRT doesn't use the Windows Timezone backend, so don't build the
Windows test.

Change-Id: I32620546de3ad1f19402cc1359f8038200c915ec
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>
WinRT: Remove Windows metadata flags from common mkspec

Winmd is not used, so there is no reason to embed it.

Change-Id: I0820256aecd9c3c71b0b0c8afa53941b03f97363
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>