media: tegra_v4l2: add dual camera support

media: tegra_v4l2: add dual camera support

Add support for dual cameras from both CSI-A and CSI-B:
 - move all the CSI settings into video buffer struct
 - queue the video buffer struct to a dedicated queue
 - process one video buffer struct from the queue at one time

Change-Id: Ibd4f56c66c479ee862c95807a7e2e57e8f8e0b34
Signed-off-by: Bryan Wu <pengw@nvidia.com>
Reviewed-on: http://git-master/r/246269
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Allen Martin <amartin@nvidia.com>