drm/tegra: Introduce tegra_drm_client structure

This structure derives from host1x_client. DRM-specific fields are moved
from host1x_client to this structure, so that host1x_client can remain
agnostic of DRM.

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

diff --cc drivers/gpu/host1x/drm/dc.c
Simple merge

diff --cc drivers/gpu/host1x/drm/drm.c
Simple merge

diff --cc drivers/gpu/host1x/drm/drm.h
Simple merge

diff --cc drivers/gpu/host1x/drm/gr2d.c
Simple merge

diff --cc drivers/gpu/host1x/drm/hdmi.c
Simple merge

diff --cc include/linux/host1x.h
Simple merge