input_id: fix detection of devices with mouse buttons

Assign ID_INPUT_MOUSE property to devices with mouse buttons and no axis.

Libinput tries to use libwacom on devices with tablet-pad capability
which are detected by ID_INPUT_TABLET_PAD=1 property so assign pointer
class by setting ID_INPUT_MOUSE=1 to devices with mouse buttons and let
libwacom override the class for Wacom pads.

src/udev/udev-builtin-input_id.c

@@ -244,7 +244,9 @@ static bool test_pointers(struct udev_device *dev,
                         is_touchscreen = true;
         }
 
-        if (has_rel_coordinates && has_mouse_button)
+        if (has_mouse_button &&
+            (has_rel_coordinates ||
+            !has_abs_coordinates)) /* mouse buttons and no axis */
                 is_mouse = true;
 
         if (is_pointing_stick)