video: tegra: host: multi channels per device

video: tegra: host: multi channels per device

- Add support to have multiple channels per device.

- set max number of channels that can be assigned to
  device in platform data.
- On channel open request assign new channel to device
  till max number of channel count.
- suspend all assigned channels on device disable clk.
- un-map all channels on device release callback.

Bug 1259844
Bug 1436477

Change-Id: Ibc1de8b036cde238b292e1ffa660dc2a796f65e8
Signed-off-by: Shridhar Rasal <srasal@nvidia.com>
Reviewed-on: http://git-master/r/387096
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>