gst/mpegstream/gstmpegpacketize.*: g_malloc() can't fail, we don't need to handle...

gst/mpegstream/gstmpegpacketize.*: g_malloc() can't fail, we don't need to handle this. Same for gst_buffer_new_and_a...

Original commit message from CVS:
* gst/mpegstream/gstmpegpacketize.c: (gst_mpeg_packetize_put),
(read_cache):
* gst/mpegstream/gstmpegpacketize.h:
g_malloc() can't fail, we don't need to handle this. Same for
gst_buffer_new_and_alloc().
* gst/mpegstream/gstmpegparse.c: (gst_mpeg_parse_chain):
klass->send_buffer() should have the same semantics as
gst_pad_push(), ie. ownership of the buffer is transfered,
so we never have to unref the buffer no matter what the flow
return value was.