Fix tablet tilt values returning bad values

[madmiraal]

Currently, InputEventMouseMotion's tilt property is wrong. With a pen that does support tilt, the tilt.y value is always 0. Furthermore, when the pen doesn't support tilt, the tilt.x value is always 0.007874 instead of 0.

This PR ensures that when a devices supports tilt that the correct tilt values in the range -1 to 1 are returned, and when a device doesn't support tilt or the tilt values returned are 0 that a Vector(0, 0) is returned.

Fixes #56428

[bruvzg]

I do not have any tablet with tilt support to test it, but changes seems fine.

Note: I assume VALUATOR_TILT* range is -x .. x and pen_tilt_*_range[0] is always negative, have not found any documentation to check it.

[akien-mga]

Thanks!

[madmiraal]

Note: I assume VALUATOR_TILT* range is -x .. x and pen_tilt_*_range[0] is always negative, have not found any documentation to check it.

Although there is no reason a driver couldn't specify a minimum greater than zero, I think it's a reasonable assumption to expect the minimum value to be <= 0. The real problem is the minimum and maximum values are not necessarily symmetrical. On my Wacom tablet, the values are -64 and 63. However, if for some obscure reason, a driver specifies a minimum greater than zero, I think it would still be correct to keep the shifted value and just scale it to be between 0 and 1 as done in this PR.