tests: tegra: Add VIC 4.1 support

The Video Image Composer (VIC) 4.1 can be found on NVIDIA Tegra186 SoCs.
It uses a different class (B1B6) that is slightly incompatible with the
class found on earlier generations.

Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>