Input: sur40 - fix V4L error path cleanup

Input: sur40 - fix V4L error path cleanup

In sur40_probe(), if video_register_device() fails, the error path jumps to
err_unreg_video. This incorrectly attempts to unregister a video device
that was never successfully registered, and fails to free the V4L2 control
handler (v4l2_ctrl_handler_free) that was initialized immediately prior.

Fix this by introducing an err_free_ctrl label to properly free the V4L2
control handler and bypass video_unregister_device() when video device
registration fails.

Reported-by: sashiko-bot@kernel.org
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Link: https://patch.msgid.link/20260616051235.1549517-2-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>