usb: ehci: Make periodic_schedules a per controller variable

Periodic schedules tracks how many int_queue-s are active, and decides whether
or not to en/disable the periodic schedule based on this. This is clearly
a per controller thing.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 093eb4b..433e703 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -246,6 +246,7 @@
 	struct QH qh_list __aligned(USB_DMA_MINALIGN);
 	struct QH periodic_queue __aligned(USB_DMA_MINALIGN);
 	uint32_t *periodic_list;
+	int periodic_schedules;
 	int ntds;
 };