media: cx231xx: Remove some deadcode

cx231xx_bcount and cx231xx_power_suspend() were added by the original
commit e0d3bafd ("V4L/DVB (10954): Add cx231xx USB driver")
but remained unused.

cx231xx_dump_HH_reg() was added by
commit 64fbf444 ("[media] cx231xx: Added support for Carraera, Shelby,
RDx_253S and VIDEO_GRABBER")
but remained unused.

Remove them.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>