drm/bridge: tc358767: switch to ->edid_read callback

Prefer using the struct drm_edid based callback and functions.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/978100cf8915b580ce66d34d27ed48858d9c161a.1706038510.git.jani.nikula@intel.com