USB: fix ehci alignment error

The Kirkwood gave an unaligned memory access error on
line 742 of drivers/usb/host/echi-hcd.c:
"ehci->last_periodic_enable = ktime_get_real();"
Signed-off-by: NHarro Haan <hrhaan@gmail.com>
Cc: stable <stable@kernel.org>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

include/linux/usb/hcd.h

@@ -178,7 +178,7 @@ struct usb_hcd {
 	 * this structure.
 	 */
 	unsigned long hcd_priv[0]
-			__attribute__ ((aligned(sizeof(unsigned long))));
+			__attribute__ ((aligned(sizeof(s64))));
 };
 
 /* 2.4 does this a bit differently ... */