USB: serial: refactor read urb submission in generic driver

Use the already exported function for submitting the read urb associated
with a usb_serial_port.

Make sure it returns the result of usb_submit_urb and rename to the
more descriptive usb_serial_generic_submit_read_urb.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h
index ab311da..53f6dc6 100644
--- a/include/linux/usb/serial.h
+++ b/include/linux/usb/serial.h
@@ -321,7 +321,7 @@
 extern void usb_serial_generic_release(struct usb_serial *serial);
 extern int usb_serial_generic_register(int debug);
 extern void usb_serial_generic_deregister(void);
-extern void usb_serial_generic_resubmit_read_urb(struct usb_serial_port *port,
+extern int usb_serial_generic_submit_read_urb(struct usb_serial_port *port,
 						 gfp_t mem_flags);
 extern int usb_serial_handle_sysrq_char(struct tty_struct *tty,
 					struct usb_serial_port *port,