Continues mode is a special mode where 2 /dev/video devices can be active
at the same time. Either the video-preview + video nodes or the
viewfinder (for still capture) + capture nodes.

For the video-preview + video-recording case modern userspace will
use a single stream multiplexed by pipewire.

The still-capture case is extra special only starting the preview
stream and then relying on a custom ATOMISP_IOC_S_CONT_CAPTURE_CONFIG
ioctl to set things up followed by a second stream on to capture
the amount of configured still pictures. While running the sensor
at full resolution all the time. This case too is better handled
with dma-buf + GPU downscaling for the view-finder rather then all this
custom special code. Besises this the ioctl expects a bunch of special
non error checked conditions to be met otherwise things will crash/hang.

The continues mode also involves a special cases all over the code
getting in the way of further cleanups and simplifying the code to
using just 1 /dev/video# node. So lets remove it and the
related custom ATOMISP_IOC_S_CONT_CAPTURE_CONFIG ioctl.

Link: https://lore.kernel.org/linux-media/ea81b17b-7d1f-a5e1-11dd-04db310e1e50@redhat.com/
Link: https://lore.kernel.org/r/20230221145906.8113-3-hdegoede@redhat.comSigned-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>