ext/mythtv/gstmythtvsrc.c: Clean up a bit, mostly the debug statements; fix deadlock in _set_property() in the error ...

Original commit message from CVS:
* ext/mythtv/gstmythtvsrc.c: (do_read_request_response),
(gst_mythtv_src_create), (gst_mythtv_src_get_position),
(gst_mythtv_src_do_seek), (gst_mythtv_src_start),
(gst_mythtv_src_next_program_chain), (gst_mythtv_src_get_size),
(gst_mythtv_src_handle_event), (gst_mythtv_src_handle_query),
(gst_mythtv_src_change_state), (gst_mythtv_src_set_property),
(gst_mythtv_src_uri_get_type):
Clean up a bit, mostly the debug statements; fix deadlock in
_set_property() in the error cases; fix up query function.