USB: ark3116: fix use-after-free in TIOCMIWAIT

USB: ark3116: fix use-after-free in TIOCMIWAIT

commit 5018860321dc7a9e50a75d5f319bc981298fb5b7 upstream.

Use the port wait queue and make sure to check the serial disconnected
flag before accessing private port data after waking up.

This is is needed as the private port data (including the wait queue
itself) can be gone when waking up after a disconnect.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>