tests/gamepads: add initial support for testing gamepads

Probably not enough, but at least this should allow to detect and test
https://patchwork.kernel.org/patch/11181161/

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
3 jobs for master in 1 minute and 55 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #761352
flake

00:01:42

passed #761353
install

00:01:41

passed #761354
install_no_man_pages

00:01:54