ext/faac/gstfaac.c: Gst09-ize code a little bit more: use gst_pad_alloc_buffer(), move event handling from chain func...

Original commit message from CVS:
* ext/faac/gstfaac.c: (gst_faac_class_init), (gst_faac_init),
(gst_faac_sink_setcaps), (gst_faac_src_setcaps),
(gst_faac_sink_event), (gst_faac_chain), (gst_faac_set_property),
(gst_faac_get_property), (gst_faac_change_state):
Gst09-ize code a little bit more: use gst_pad_alloc_buffer(),
move event handling from chain function into an event function,
add some locks here and there, do some cleanups; disable 32-bit
integer and float input formats until we're sure that those
actually work (couldn't play back the produced files with
anything).