dw_dmac: fix copy/paste bug in tasklet

The tasklet checks RAW.BLOCK twice, and does not check RAW.XFER. This is
obviously wrong, and could theoretically cause the driver to hang.

Reported-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/dma/dw_dmac.c

@@ -364,7 +364,7 @@ static void dw_dma_tasklet(unsigned long data)
 	int i;
 
 	status_block = dma_readl(dw, RAW.BLOCK);
-	status_xfer = dma_readl(dw, RAW.BLOCK);
+	status_xfer = dma_readl(dw, RAW.XFER);
 	status_err = dma_readl(dw, RAW.ERROR);
 
 	dev_vdbg(dw->dma.dev, "tasklet: status_block=%x status_err=%x\n",