media: tegra: Tegra videobuf2

This is based off of videobuf2-dma-contig, except we use Tegra's
nvmap for the buffer allocations.

Signed-off-by: Andrew Chew <achew@nvidia.com>
Change-Id: I15e689c33ee7b4fc0aade794c78701c82483df3f
Reviewed-on: http://git-master/r/145345
(cherry picked from commit 70a4f20fbdd6c2c719400d6c59ef58d845657031)

Signed-off-by: Bryan Wu <pengw@nvidia.com>
Change-Id: Ia0632d7fcb28415e33fbb22c48f29117d7436f1d
Reviewed-on: http://git-master/r/170824
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Andrew Chew <achew@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Winnie Hsu <whsu@nvidia.com>