This way the drm_bridge_funcs interface is consistent with the rest of
the subsystem.

The drivers implementing those hooks are patched too.

v10:
* Add changelog to the commit message

v8 -> v9:
* No changes

v7:
* Adjust things to the bridge_state changes

v6:
* Also fixed rcar-du/rcar_lvds.c same as analogix/analogix_dp_core.c

v5:
* No changes

v4:
* Rename func params into old_bridge_state
* Add Laurent's Rb

v3:
* Old state clarification moved to a separate patch

v2:
* Pass the old bridge state
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: renamed state as old_bridge_state in rcar_lvds_atomic_disable]
Reviewed by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-5-boris.brezillon@collabora.com