drm/bridge: sn65dsi83: Fix bridge removal

Commit 24417d5b ("drm/bridge: ti-sn65dsi83: Implement .detach
callback") moved the unregistration of the bridge DSI device and bridge
itself to the detach callback.

While this is correct for the DSI device detach and unregistration, the
bridge is added in the driver probe, and should thus be removed as part
of its remove callback.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Fixes: 24417d5b ("drm/bridge: ti-sn65dsi83: Implement .detach callback")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20211025151536.1048186-14-maxime@cerno.tech