USB: FIX bitfield istl_flip:1, make it unsigned.

istl_flip is a signed bitfield of one bit so it can be -1 or 0.
However in drivers/usb/host/isp1362-hcd.c:1103:

finish_iso_transfers(isp1362_hcd,
	&isp1362_hcd->istl_queue[isp1362_hcd->istl_flip]);

So if isp1362_hcd->istl_flip is set, the 2nd argument becomes
&isp1362_hcd->istl_queue[-1], which is invalid.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/isp1362.h

@@ -534,8 +534,8 @@ struct isp1362_hcd {
 
 	/* periodic schedule: isochronous */
 	struct list_head	isoc;
-	int			istl_flip:1;
-	int			irq_active:1;
+	unsigned int		istl_flip:1;
+	unsigned int		irq_active:1;
 
 	/* Schedules for the current frame */
 	struct isp1362_ep_queue atl_queue;