video: tegra: dsi: add new ganged mode parameters

video: tegra: dsi: add new ganged mode parameters

* Add support for left/right ganged mode with overlap
  region
* Add ability to swap DSIA and DSIB in ganged mode, for
  panels where DSIB connects to the master DSI controller IC.
* Add ability to write DSI host and panel commands to both
  links instead of just to the master link

Bug 1614907

Change-Id: Ib7ccfe6a1b61317a768568c74893d39b3ebf3cf8
Signed-off-by: Daniel Solomon <daniels@nvidia.com>
Reviewed-on: http://git-master/r/711289
Reviewed-by: Mitch Luban <mluban@nvidia.com>
Tested-by: Mitch Luban <mluban@nvidia.com>