mmc: fix spares errors of sdhci.c

1. sdhci_prepare_data: fix shadowing of count variable
	u8 count
	int count -> sg_cnt;
2.  sdhci_add_host: assignment of integer to pointer
	dma_mask = 0 -> dma_mask = NULL;

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index d3e4a39..13bd681 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -672,14 +672,14 @@
 					host->ioaddr + SDHCI_ADMA_ADDRESS);
 			}
 		} else {
-			int count;
+			int sg_cnt;
 
-			count = dma_map_sg(mmc_dev(host->mmc),
+			sg_cnt = dma_map_sg(mmc_dev(host->mmc),
 					data->sg, data->sg_len,
 					(data->flags & MMC_DATA_READ) ?
 						DMA_FROM_DEVICE :
 						DMA_TO_DEVICE);
-			if (count == 0) {
+			if (sg_cnt == 0) {
 				/*
 				 * This only happens when someone fed
 				 * us an invalid request.
@@ -1583,7 +1583,7 @@
 
 	/* XXX: Hack to get MMC layer to avoid highmem */
 	if (!(host->flags & SDHCI_USE_DMA))
-		mmc_dev(host->mmc)->dma_mask = 0;
+		mmc_dev(host->mmc)->dma_mask = NULL;
 
 	host->max_clk =
 		(caps & SDHCI_CLOCK_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;