usb: hub: Change USB hub descriptor to match USB 3.0 hubs

USB 3.0 hubs have a slightly different hub descriptor than USB 2.0
hubs, with a fixed (rather than variable length) size. Change the
host controller drivers that access those last two fields
(DeviceRemovable and PortPowerCtrlMask) to use the union.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 59ee476..d5a1b34 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -50,8 +50,8 @@
 		cpu_to_le16(0x8), /* wHubCharacteristics */
 		10,		/* bPwrOn2PwrGood */
 		0,		/* bHubCntrCurrent */
-		{},		/* Device removable */
-		{}		/* at most 7 ports! XXX */
+		{		/* Device removable */
+		}		/* at most 7 ports! XXX */
 	},
 	{
 		0x12,		/* bLength */