tty: Fix USB kref leak

The sysrq code acquired a kref leak. Fix it by passing the tty separately
from the caller (thus effectively using the callers kref which all the
callers hold anyway)

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 3dc3768..5f08702 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -2121,7 +2121,7 @@
 				/* Note that the error flag is duplicated for
 				   every character received since we don't know
 				   which character it applied to */
-				if (!usb_serial_handle_sysrq_char(port,
+				if (!usb_serial_handle_sysrq_char(tty, port,
 						data[packet_offset + i]))
 					tty_insert_flip_char(tty,
 						data[packet_offset + i],