usb: musb: remove unused pipe variable

This patch fix the following build warning:
drivers/usb/musb/musb_host.c:1809:8: warning: variable 'pipe' set but not used [-Wunused-but-set-variable]
by removing the pipe variable in musb_host_rx()
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/musb/musb_host.c

@@ -1779,7 +1779,6 @@ void musb_host_rx(struct musb *musb, u8 epnum)
 	struct musb_qh		*qh = hw_ep->in_qh;
 	size_t			xfer_len;
 	void __iomem		*mbase = musb->mregs;
-	int			pipe;
 	u16			rx_csr, val;
 	bool			iso_err = false;
 	bool			done = false;
@@ -1808,8 +1807,6 @@ void musb_host_rx(struct musb *musb, u8 epnum)
 		return;
 	}
 
-	pipe = urb->pipe;
-
 	trace_musb_urb_rx(musb, urb);
 
 	/* check for errors, concurrent stall & unlink is not really