dmaengine: usb-dmac: remove unused ‘uchan’

In usb_dmac_of_xlate(), variable ‘uchan’ is initialized but never used, which
leads to warning with W=1

drivers/dma/sh/usb-dmac.c: In function ‘usb_dmac_of_xlate’:
drivers/dma/sh/usb-dmac.c:655:24: warning: variable ‘uchan’ set but not used [-Wunused-but-set-variable]
  struct usb_dmac_chan *uchan;

So remove it.

Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

drivers/dma/sh/usb-dmac.c

@@ -652,7 +652,6 @@ static bool usb_dmac_chan_filter(struct dma_chan *chan, void *arg)
 static struct dma_chan *usb_dmac_of_xlate(struct of_phandle_args *dma_spec,
 					  struct of_dma *ofdma)
 {
-	struct usb_dmac_chan *uchan;
 	struct dma_chan *chan;
 	dma_cap_mask_t mask;
 
@@ -667,8 +666,6 @@ static struct dma_chan *usb_dmac_of_xlate(struct of_phandle_args *dma_spec,
 	if (!chan)
 		return NULL;
 
-	uchan = to_usb_dmac_chan(chan);
-
 	return chan;
 }