USB: gadget: dummy_hcd: fix hub-descriptor removable fields

Flag the first and only port as removable while also leaving the
remaining bits (including the reserved bit zero) unset in accordance
with the specifications:

	"Within a byte, if no port exists for a given location, the bit
	field representing the port characteristics shall be 0."

Also add a comment marking the legacy PortPwrCtrlMask field.

Fixes: 1cd8fd2887 ("usb: gadget: dummy_hcd: add SuperSpeed support")
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: Tatyana Brokhman <tlinder@codeaurora.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/udc/dummy_hcd.c

@@ -2008,7 +2008,7 @@ ss_hub_descriptor(struct usb_hub_descriptor *desc)
 			HUB_CHAR_COMMON_OCPM);
 	desc->bNbrPorts = 1;
 	desc->u.ss.bHubHdrDecLat = 0x04; /* Worst case: 0.4 micro sec*/
-	desc->u.ss.DeviceRemovable = 0xffff;
+	desc->u.ss.DeviceRemovable = 0;
 }
 
 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
@@ -2020,8 +2020,8 @@ static inline void hub_descriptor(struct usb_hub_descriptor *desc)
 			HUB_CHAR_INDV_PORT_LPSM |
 			HUB_CHAR_COMMON_OCPM);
 	desc->bNbrPorts = 1;
-	desc->u.hs.DeviceRemovable[0] = 0xff;
-	desc->u.hs.DeviceRemovable[1] = 0xff;
+	desc->u.hs.DeviceRemovable[0] = 0;
+	desc->u.hs.DeviceRemovable[1] = 0xff;	/* PortPwrCtrlMask */
 }
 
 static int dummy_hub_control(