ext/ogg/gstogmparse.c: Don't remove/re-add source pad if the new caps are the same as the old caps anyway (#333042). ...

Original commit message from CVS:
* ext/ogg/gstogmparse.c: (gst_ogm_audio_parse_init),
(gst_ogm_video_parse_init), (gst_ogm_text_parse_init),
(gst_ogm_parse_sink_convert), (gst_ogm_parse_sink_query),
(gst_ogm_parse_chain):
Don't remove/re-add source pad if the new caps are the same as
the old caps anyway (#333042). When removing source pad, don't
unref it afterwards - we didn't ref it when adding. Sprinkle some
GST_DEBUG_FUNCPTR goodness here and there. Don't leak references
after using gst_pad_get_parent(). Return downstream flow return
value in chain function.