drm/tegra: Rename gr2d to tegra-gr2d
drm/tegra: Rename gr2d to tegra-gr2d

Other drivers use the tegra- prefix in their names, so add it to this
driver's name as well for consistency.

Signed-off-by: Thierry Reding <3055038c414aef68bf32c33b8118623e7554e0f2@nvidia.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs