wayland: remove set_user_data from seat_listener

The user_data is passed on add_listener and can later be changed with
set_user_data. But because we don't want to change it later and because it is
the same object remove the set_user_data call.

This might be a copy&paste leftover from the initial draft for the wayland
backend.

video/out/wayland_common.c

@@ -444,7 +444,6 @@ static void seat_handle_capabilities(void *data,
 
     if ((caps & WL_SEAT_CAPABILITY_KEYBOARD) && !wl->input.keyboard) {
         wl->input.keyboard = wl_seat_get_keyboard(seat);
-        wl_keyboard_set_user_data(wl->input.keyboard, wl);
         wl_keyboard_add_listener(wl->input.keyboard, &keyboard_listener, wl);
     }
     else if (!(caps & WL_SEAT_CAPABILITY_KEYBOARD) && wl->input.keyboard) {
@@ -453,7 +452,6 @@ static void seat_handle_capabilities(void *data,
     }
     if ((caps & WL_SEAT_CAPABILITY_POINTER) && !wl->input.pointer) {
         wl->input.pointer = wl_seat_get_pointer(seat);
-        wl_pointer_set_user_data(wl->input.pointer, wl);
         wl_pointer_add_listener(wl->input.pointer, &pointer_listener, wl);
     }
     else if (!(caps & WL_SEAT_CAPABILITY_POINTER) && wl->input.pointer) {