Mouse sensitivity fix + aligning ranges

[ryandeering]

I noticed that the application of the mouse sensitivity when set to maximum seems to be a bit broken while working on my Switch port. It would initialise with 1.0 even though it would be set to 2.5 in fallout2.cfg and not change if I set it to max. I built on Windows to be sure, and it seems it's properly applied now.

I also just fixed the range as it only goes from 1.0 to 2.5.

Thanks!