linux-phytec-ti

drm/tegra: Add minimal power management

For now only disable the KMS hotplug polling helper logic upon suspend
and re-enable it on resume.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Mark Zhang <markz@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>