USB: Sierra: fix oops upon device close

This patch (as1263) fixes a mixup that occurred when conflicting
patches for the sierra driver were merged incorrectly. The former
sierra_shutdown routine should have been become sierra_release, not
sierra_disconnect.

The symptom this fixes is an oops when the device file is closed after
a Sierra device has been unplugged (Bugzilla #13675).

Signed-off-by: Alan Stern <[e-mail]>
Tested-by: Peter Naulls <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/serial/sierra.c

···
 	return 0;
 }
 
-static void sierra_disconnect(struct usb_serial *serial)
+static void sierra_release(struct usb_serial *serial)
 {
 	int i;
 	struct usb_serial_port *port;
···
 		if (!portdata)
 			continue;
 		kfree(portdata);
-		usb_set_serial_port_data(port, NULL);
 	}
 }
 
···
 	.tiocmget          = sierra_tiocmget,
 	.tiocmset          = sierra_tiocmset,
 	.attach            = sierra_startup,
-	.disconnect        = sierra_disconnect,
+	.release           = sierra_release,
 	.read_int_callback = sierra_instat_callback,
 };