QClipboard Windows debugging: fix compilation with VS2005.

This patch based on Qt Creator allows Qt 4 to be built using VS2005

[ChangeLog][Windows] Fixes build with MSVC 2005

Task-number: QTBUG-39133
Change-Id: I413beb063b5d1f458cfa26f54f6bbd2de9240380
Reviewed-by: Andy Shaw <andy.shaw@digia.com>