gst/gstelement.c (gst_element_change_state_func): Renamed from gst_element_change_state, variable name changes.

Original commit message from CVS:
2005-10-10  Andy Wingo  <wingo@pobox.com>

* gst/gstelement.c (gst_element_change_state_func): Renamed from
gst_element_change_state, variable name changes.
(gst_element_change_state): Split out of gst_element_set_state in
preparation for the state change merge. Doesn't pay attention to
the 'transition' argument.
(gst_element_set_state): Updates, hopefully purely cosmetic.
(gst_element_sync_state_with_parent): MT-safety. Ported from the
state change patch.
(gst_element_get_state_func): Renamed from get_state, cosmetic
changes.