usb: r8a66597-udc: fix spinlock usage

Because the disconnect function in the composite driver will call spin_lock,
this driver has to call spin_unlock before calling driver->disconnet().
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/r8a66597-udc.c

@@ -1083,7 +1083,9 @@ static void irq_device_state(struct r8a66597 *r8a66597)
 
 	if (dvsq == DS_DFLT) {
 		/* bus reset */
+		spin_unlock(&r8a66597->lock);
 		r8a66597->driver->disconnect(&r8a66597->gadget);
+		spin_lock(&r8a66597->lock);
 		r8a66597_update_usb_speed(r8a66597);
 	}
 	if (r8a66597->old_dvsq == DS_CNFG && dvsq != DS_CNFG)