Blender Git Loki

Fix T40717: Screen does not update while scrolling or zooming with touchpad on a laptop

This is rather workaround solution for now, which seems to
work and it's not that huge to maintain (one liner apart from
the comment).

Idea is to make sure PeekMessage peeks the message when window
proc receives WM_MOUSEWHEEL (some touchpad drivers seems to
swallow the messages making it so PeekMessage doesn't get
anything).