staging: mt7621-mmc: Remove unused field sg from msdc_dma

The field sg from struct msdc_dma is once set and never read, so
remove it.
Signed-off-by: Christian Lütke-Stetzkamp <christian@lkamp.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/mt7621-mmc/mt6575_sd.h

@@ -480,7 +480,6 @@ struct bd {
 
 struct msdc_dma {
 	u32 sglen;                   /* size of scatter list */
-	struct scatterlist *sg;      /* I/O scatter list */
 
 	struct gpd *gpd;                  /* pointer to gpd array */
 	struct bd  *bd;                   /* pointer to bd array */

drivers/staging/mt7621-mmc/sd.c

@@ -1041,7 +1041,6 @@ static void msdc_dma_setup(struct msdc_host *host, struct msdc_dma *dma,
 
 	BUG_ON(sglen > MAX_BD_NUM); /* not support currently */
 
-	dma->sg = sg_cmd;
 	dma->sglen = sglen;
 
 	N_MSG(DMA, "DMA sglen<%d> xfersz<%d>", sglen, host->xfer_size);