Fix mouse scroll for key mapping

[LunaMoo]

Fixes #11043 (which I totally forgot about;p ~ sorries)

[LunaMoo]

Please don't merge yet, it causes some weird wheel interaction in UI;c, I guess it needs that fix has to be limited to in-game similar to how mouse movement is.

[LunaMoo]

Heh, I think it's still bad overall, going to have to think about it more as it can get stuck.
Does WM_MOUSEWHEEL is only called when a wheel event is passed? Or maybe something related to #11226

[LunaMoo]

As far as I tested this works fine now althrough may be a bit hacky. I set a variable in WM_MOUSEWHEEL event when wheel is "key_down" and check for that variable under default case to send "key_up".

Moved WM_MOUSEWHEEL to DisplayProc as well, dunno what "some reason" was forcing it in WndProc, but works fine nowadays in DisplayProc.

If this solution is acceptable I can squash the commits later.

[LunaMoo]

Heh I squashed, but it still sucks I need to release it elsewhere, default case in DisplayProc still requires some event to trigger I guess.

[LunaMoo]

Ended up using a timer using 16ms delay to ensure wheel is released on next frame even in 60 fps games. I think it's ready now.:]

[hrydgard]

Yeah, I suppose that'll be alright...