drm/bridge: Add I2C based driver for ps8622/ps8625 bridge

This patch adds drm_bridge driver for parade DisplayPort
to LVDS bridge chip.

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rahul Sharma <rahul.sharma@samsung.com>
Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
Acked-by: Inki Dae <inki.dae@samsung.com>
Tested-by: Rahul Sharma <rahul.sharma@samsung.com>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Tested-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
[treding@nvidia.com: break cyclic dependency, add KMS helper dependency]
Signed-off-by: Thierry Reding <treding@nvidia.com>