call itdb_shuffle_write in itdb_write if needed
call itdb_shuffle_write in itdb_write if needed

Until now, library users have to call itdb_shuffle_write by
themselves when handling an iPod Shuffle. Since libgpod generally
know when it's handling a Shuffle, it makes sense to do it
automatically.

hyperair/libgpod,neuschaefer/libgpod,hyperair/libgpod,neuschaefer/libgpod,hyperair/libgpod,hyperair/libgpod,neuschaefer/libgpod,hyperair/libgpod,neuschaefer/libgpod,neuschaefer/libgpod