USB: remove unnecessary type casting of urb->context

urb->context code cleanup

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/serial/safe_serial.c b/drivers/usb/serial/safe_serial.c
index e6acac4..94bddf0 100644
--- a/drivers/usb/serial/safe_serial.c
+++ b/drivers/usb/serial/safe_serial.c
@@ -195,7 +195,7 @@
 
 static void safe_read_bulk_callback (struct urb *urb)
 {
-	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
+	struct usb_serial_port *port =  urb->context;
 	unsigned char *data = urb->transfer_buffer;
 	unsigned char length = urb->actual_length;
 	int result;