test: write resolution for uinput devices after creating the device

EVIOCSABS allows us to set the device's abs axes to the desired resolution.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
test: fix up the tests to test for resolution now too

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
test: don't set the abs value when initializing an uinput device

The helper function uses abs.value for the axis code (to save a parameter).
Reset that to 0 before we write to the device

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
test: constify the input_absinfo argument

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
test: define a common device name

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>