Fix raw input mouse position jumping after window state changes

[PoloniumRain]

This fixes multiple Windows raw input issues that can occur after the window state changes, which can cause the mouse pointer to jump around and make incorrect selections on the menu.

Things that can cause this to happen:

1. Switching between windowed and fullscreen modes.
2. Window resizes, such as those triggered by cores.
3. Losing and regaining window focus while in windowed mode.

It's hard to describe exactly how to reproduce each issue, so i've created the video below which shows the behaviour before and after this fix:

Comparison.mp4

The behaviour can vary depending on what menu item was previously selected before the window resize/refocus happened, but it's all the same kind of problems where the mouse jumps around and will do something unintended when clicked. This PR fixes all of these issues by syncing the internal mouse coordinates with the OS cursor position when these window state changes occur.

The raw input mouse behaviour now also matches dinput in these cases (dinput does not have any of these issues).

[sonninnos]

Please keep the code C89 compliant and why not also put that last_focus static bool in the existing winraw_input_t struct instead.

[PoloniumRain]

@sonninnos Ok, done. To be honest i'm still learning this stuff and completely forgot about C89 😅

[sonninnos]

Nice. Might as well put that old winraw_focus in the struct too while at it and make both as bools.