tty: nozomi, fix tty refcounting bug

Don't forget to drop a tty refererence on fail paths in
receive_data().

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>