staging: media: tegra-video: move tegra_channel_fmt_align to a per-soc op

tegra_channel_fmt_align() takes care of the size constraints, alignment and
rounding requirements of the Tegra210 VI peripheral. Tegra20 has different
constraints.

In preparation for adding Tegra20 support, move this function to a new op
in the soc-specific `struct tegra_vi_ops` .

Also move to tegra210.c the T210-specific defines used in the moved code.

No functional changes.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>