video: tegra: host: fix array access beyond size

video: tegra: host: fix array access beyond size

- fixes boundary access of syncpt/waitbases array.
- few NULL check for memory allocation in nvhost.

Change-Id: I8912276b104a72fa4035d47a8e232643d1fd9a32
Signed-off-by: Shridhar Rasal <srasal@nvidia.com>
Reviewed-on: http://git-master/r/414138
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Arto Merilainen <amerilainen@nvidia.com>
Reviewed-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>