[WIP] universal gamepad support

[p3r7]

this PR provides (almost) universal gamepad support

in its current state, it works pretty well on my norns with the 3 controllers I have tested with.

how?

this PR removes the use of custom gamepad profiles as lua files and instead relies on the SDL controller profile database.

i didn't use those profiles in the first place as they were lacking the info of analog sensors resolution (EV_ABS, ABS for absolute),

but i discovered that those resolutions could be retrieved with a call to libevdev_get_abs_info.

by combining the 2, we're 100% compatible with our old custom profile logic.

i didn't know this was possible, as SDL itself seems to not look up this info and hard-codes resolution in its code source for a selected number of controllers. e.g.:

i guess they do that do be as platform-agnostic as possible...

what's next to do

everything works fine but i'm getting this error message in the matron logs when i plug a controller. everything seems to work though. idk if it was occurring before my patch or not but i may be doing something wrong.

   dev_monitor: skipping node-less entry in /dev/input
   failed to init libevdev (Invalid argument)
   dev_list_add: error allocating device data

also i just dropped the SDL gamepad db file under lua/core/gamecontrollerdb.txt. but it may be smarter to grab it as a git submodule. what do you think about it?

also i'd certainly merge the gamepad_db.lua and gamepad.lua files into one.

[Dewb]

What is the test procedure to verify that a controller works as expected with the new arrangement? My collection of older stuff is unfortunately in storage at the moment but I have some 8bitdo and Microsoft units handy.

[p3r7]

progressed a bit more on this. there are still some optims & simplifications here & there i'd like to make. i also realized that the gamepad.dpad callback doesn't fire properly so i should fix that as well.

but i'm getting close to having something mergeable.

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What is the test procedure to verify that a controller works as expected with the new arrangement?

i just made a script for that: gamepad-monitor.

otherwise navigating in the global menu is another way to test (though not as extensive).