USB: serial: kl5kusb105: fix open error path

commit 6774d5f53271d5f60464f824748995b71da401ab upstream.

Kill urbs and disable read before returning from open on failure to
retrieve the line state.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>