Analog stick and button mapping

[azihassan]

Adding support for the analog stick would allow for the D-pad buttons to be mapped to other types of functionality. I already attempted it here, and even though the relevant logs do show up in the console, the events don't register in the settings menu.

It also looks like the X and Y (or A and B) buttons are flipped in the settings menu (button presses produce the wrong event value). These were defined here:

devilutionX/CMake/platforms/dreamcast.cmake

Line 38 in eed507a

set(JOY_BUTTON_A 2)

[AJenbo]

Buttons being swapped seams to be an upstream issue.