drm/bridge: Fix free wrong object in sii8620_init_rcp_input_dev

drm/bridge: Fix free wrong object in sii8620_init_rcp_input_dev

rc_dev is allocated by rc_allocate_device(), and doesn't assigned to
ctx->rc_dev before calling  rc_free_device(ctx->rc_dev).
So it should call rc_free_device(rc_dev);

Fixes: e25f1f7c94e1 ("drm/bridge/sii8620: add remote control support")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211227092522.21755-1-linmq006@gmail.com