contrib: qtbase: backport patch `d3d: Drive window updates from a vblank watcher thread`

There is not much to write here, as the patch itself describes it pretty well. The target issue is here: https://bugreports.qt.io/browse/QTBUG-127267.

I manually add this patch because it is not clear if we are going to stay on Qt 6.8 until the next LTS release (6.11), or update to 6.9. And I believe that this is important enough that we should not wait until the next LTS, which is at the earliest in 2026.

The only change was done using Q_LOGGING_CATEGORY instead of Q_STATIC_LOGGING_CATEGORY, which is not available in Qt 6.8.

I have tested on Windows 10 (VM), and Windows 7 (VM) (this patch does not mean anything on Windows 7, as we use OpenGL there, but I checked if it broke). Later today, I will try to test on Windows 11 with Nvidia graphics.

Request review @chub, @robUx4.