gst/Makefile.am: remove gstcpu.[ch].  The gst_cpu functionality is broken and should be implemented in a different li...

Original commit message from CVS:
* gst/Makefile.am: remove gstcpu.[ch].  The gst_cpu functionality
is broken and should be implemented in a different library.
* gst/gst.c: (init_post): don't call _gst_cpu_initialize()
* gst/gst.h: remove gstcpu.h
* gst/gstcpu.c: remove
* gst/gstcpu.h: remove
* gst/Makefile.am.future: Remove this file.  It's ancient.