usb: gadget: f_ncm: allow using NCM in SuperSpeed Plus gadgets.

Currently, enabling f_ncm at SuperSpeed Plus speeds results in an
oops in config_ep_by_speed because ncm_set_alt passes in NULL
ssp_descriptors. Fix this by re-using the SuperSpeed descriptors.
This is safe because usb_assign_descriptors calls
usb_copy_descriptors.

Tested: enabled f_ncm on a dwc3 gadget and 10Gbps link, ran iperf
Reviewed-by: NMaciej Żenczykowski <maze@google.com>
Signed-off-by: NLorenzo Colitti <lorenzo@google.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

drivers/usb/gadget/function/f_ncm.c

@@ -1536,7 +1536,7 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 		fs_ncm_notify_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
-			ncm_ss_function, NULL);
+			ncm_ss_function, ncm_ss_function);
 	if (status)
 		goto fail;