xhci: trivial: Remove assigned but unused ep_ctx.

Remove the variable ep_ctx from xhci_add_endpoint(), since it is
assigned but unused.  Caught by Coverity.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

drivers/usb/host/xhci.c

@@ -1627,7 +1627,6 @@ int xhci_add_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
 	struct xhci_hcd *xhci;
 	struct xhci_container_ctx *in_ctx, *out_ctx;
 	unsigned int ep_index;
-	struct xhci_ep_ctx *ep_ctx;
 	struct xhci_slot_ctx *slot_ctx;
 	struct xhci_input_control_ctx *ctrl_ctx;
 	u32 added_ctxs;
@@ -1663,7 +1662,6 @@ int xhci_add_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
 	out_ctx = virt_dev->out_ctx;
 	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
 	ep_index = xhci_get_endpoint_index(&ep->desc);
-	ep_ctx = xhci_get_ep_ctx(xhci, out_ctx, ep_index);
 
 	/* If this endpoint is already in use, and the upper layers are trying
 	 * to add it again without dropping it, reject the addition.