media: tegra-video: Add support for x8 captures with gang ports

Tegra VI/CSI hardware don't have native 8 lane capture support.

Each CSI port has max 4 lanes only. So for x8 captures, consecutive
ports are ganged up for left half and right half captures on to each
x4 ports with buffer offsets based on source image split width to align
side-by-side.

All ports in gang are configured together during the corresponding
video device node streaming for x8 captures.

x8 capture with gang ports are supported with HDMI-to-CSI bridges
where they split 4K image into left half onto one x4 port and
right half onto second x4 port.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>