Series of fixes for dereferenced pointers that gcc 4.1 complains about.

Series of fixes for dereferenced pointers that gcc 4.1 complains about.

Original commit message from CVS:
reviewed by: <delete if not using a buddy>
* gst/gstbin.c: (gst_bin_dispose), (gst_bin_provide_clock_func),
(gst_bin_handle_message_func):
* gst/gstclock.c: (gst_clock_dispose), (gst_clock_set_master):
* gst/gstelement.c: (gst_element_set_clock), (gst_element_dispose),
(gst_element_set_bus_func):
* gst/gstghostpad.c: (gst_proxy_pad_dispose):
* gst/gstminiobject.c: (gst_value_set_mini_object),
(gst_value_take_mini_object):
* gst/gstpad.c: (gst_pad_set_pad_template):
* gst/gstpipeline.c: (gst_pipeline_dispose),
(gst_pipeline_use_clock), (gst_pipeline_auto_clock):
* libs/gst/base/gstcollectpads.c: (gst_collect_pads_pop),
(gst_collect_pads_chain):
* libs/gst/net/gstnettimeprovider.c:
(gst_net_time_provider_set_property):
Series of fixes for dereferenced pointers that gcc 4.1 complains about.
It's in fact all issues with gst_*object_replace().