drm/bridge: do not pass drm_bridge_funcs to drm_bridge_init

Assign the pointer to bridge ops structure(drm_bridge_funcs) in
the bridge driver itself, instead of passing it to drm_bridge_init.

This will allow bridge driver developer to pack bridge private
information inside the bridge object and pass only the drm-relevant
information to drm_bridge_init.

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