xwayland: Fix check logic in sprite_check_lost_focus()

When pointer leaves from a X window, and enters to a wayland window, the focus will lost and sprite_check_lost_focus() should return TRUE. But now the last_xwindow remains the same which will defeat the current logic in sprite_check_lost_focus() because IsParent() will be FALSE in this case.

To fix the issue, also check whether last_xwindow is the window itself.

Signed-off-by: Morose chenlinxiang@kylinos.cn