[PATCH] USB: fix error paths in kobil_sct

some error codes are incorrect and there's an URB leak in an error path.

drivers/usb/serial/kobil_sct.c

@@ -262,7 +262,7 @@ static int kobil_open (struct usb_serial_port *port, struct file *filp)
 	// allocate memory for transfer buffer
 	transfer_buffer = (unsigned char *) kmalloc(transfer_buffer_length, GFP_KERNEL);  
 	if (! transfer_buffer) {
-		return -1;
+		return -ENOMEM;
 	} else {
 		memset(transfer_buffer, 0, transfer_buffer_length);
 	}
@@ -274,7 +274,7 @@ static int kobil_open (struct usb_serial_port *port, struct file *filp)
 		if (!port->write_urb) {
 			dbg("%s - port %d usb_alloc_urb failed", __FUNCTION__, port->number);
 			kfree(transfer_buffer);
-			return -1;
+			return -ENOMEM;
 		}
 	}
 
@@ -282,7 +282,9 @@ static int kobil_open (struct usb_serial_port *port, struct file *filp)
 	port->write_urb->transfer_buffer = (unsigned char *) kmalloc(write_urb_transfer_buffer_length, GFP_KERNEL);
 	if (! port->write_urb->transfer_buffer) {
 		kfree(transfer_buffer);
-		return -1;
+		usb_free_urb(port->write_urb);
+		port->write_urb = NULL;
+		return -ENOMEM;
 	} 
 
 	// get hardware version