gst/autoplug/: Fix autoplugging in spider element, so it works with new caps.

gst/autoplug/: Fix autoplugging in spider element, so it works with new caps.

Original commit message from CVS:
2003-12-22  Benjamin Otte  <in7y118@public.uni-hamburg.de>

* gst/autoplug/gstsearchfuncs.c: (gst_autoplug_caps_intersect):
* gst/autoplug/gstspideridentity.c: (gst_spider_identity_link),
(gst_spider_identity_getcaps), (gst_spider_identity_change_state),
(gst_spider_identity_sink_loop_type_finding):
* gst/autoplug/gstspideridentity.h:
Fix autoplugging in spider element, so it works with new caps.
This was mainly caused by identifying empty caps incorrectly.