Fix Windows compilation for ARMv7 (32-bits)

[AldoMX]

Historical Context

StepMania AMX was the first version to include Touch controls and support the original Microsoft Surface. I don't expect to have significant issues to compile the game for ARMv7 (32-bits).

What needs to be done?

Fix the issues reported by the compiler.

Stretch goals

If the issues are trivial, identify the commits where the affected lines were last updated and create new commits with the ARM fixes. This counts as rewriting history, but it would be fun to have old versions working on the Surface RT.