USB: EHCI: add need_io_watchdog flag to ehci_hcd

Basically the io watchdog is only useful for those quirk HCDs. For most
good ones, it only brings unnecessary wakeups.  At least, I know the
Intel EHCI HCDs should turn off the flag.

Signed-off-by: Alek Du <alek.du@intel.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 48b9e88..acec108 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -126,6 +126,7 @@
 	unsigned		big_endian_mmio:1;
 	unsigned		big_endian_desc:1;
 	unsigned		has_amcc_usb23:1;
+	unsigned		need_io_watchdog:1;
 
 	/* required for usb32 quirk */
 	#define OHCI_CTRL_HCFS          (3 << 6)