For specific tests we need something that e.g. looks like a touchpad, but has
a different name, a different number of slots, etc. In this case, the
following code will do exactly that:

struct input_absinfo overrides[] = {
 { .value = ABS_MT_SLOT, .minimum = 0, .maximum = 100 },
 { .value = -1 },
};

litest_create_device_with_overrides(LITEST_SYNAPTICS_CLICKPAD,
				    NULL, NULL, &overrides, NULL);

For general event codes, overrides can only add to the set of events, they
can't remove.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>