max_register is currently set to 0x1000. This is beyond the mapped
address range of the hardware, so attempts to dump the regmap from
debugfs would trigger a kernel exception.

Furthermore, the useful registers only occupy a small section at the
beginning of the full range. Change the value to 0x9c, the last known
register on the V3s and H3.

On the A31, the register range is extended to support additional
capture channels. Since this is not yet supported, ignore it for now.

Fixes: 5cc7522d ("media: sun6i: Add support for Allwinner CSI V3s")

Cc: <stable@vger.kernel.org>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>