staging: crystalhd: trim register defines

We don't actually need most of the register defines to build,
and most of the ones we don't need aren't currently interesting.

We'll leave a full copy of all of them in libcrystalhd's source,
and only include what we need and/or think might be interesting
in the driver.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>