ohci: Add missing cache-flush for hcca area

We need to cache-flush the hcca area after the initial memset, otherwise
on the first hc_interrupt we might see an old $random value as done_head and
try to interpret that as the address for a completed td (followed by chaos).

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index 9bde2b2..ccbfc02 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -2205,6 +2205,7 @@
 	if (!ohci->hcca)
 		return -ENOMEM;
 	memset(ohci->hcca, 0, sizeof(struct ohci_hcca));
+	flush_dcache_hcca(ohci->hcca);
 
 	if (hc_reset(ohci) < 0)
 		return -EIO;