[media] V4L: Add capability flags for memory-to-memory devices

[media] V4L: Add capability flags for memory-to-memory devices

This patch adds new V4L2_CAP_VIDEO_M2M and V4L2_CAP_VIDEO_M2M_MPLANE
capability flags that are intended to be used for memory-to-memory (M2M)
devices, instead of ORed V4L2_CAP_VIDEO_CAPTURE and V4L2_CAP_VIDEO_OUTPUT.

V4L2_CAP_VIDEO_M2M flag is added at the drivers, CAPTURE and OUTPUT
capability flags are left untouched and will be removed in future,
after a transition period required for existing applications to be
adapted to check only for V4L2_CAP_VIDEO_M2M.

Signed-off-by: Sylwester Nawrocki <[email protected]>
Signed-off-by: Kyungmin Park <[email protected]>
Acked-by: Kamil Debski <[email protected]>
Acked-by: Andrzej Pietrasiewicz <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>