mmc: bcm283x: fix int to pointer cast

On build with 32 bit, there is a warning for int-to-pointer-cast.
Fix the int to pointer cast by using uintptr_t.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
diff --git a/drivers/mmc/bcm2835_sdhci.c b/drivers/mmc/bcm2835_sdhci.c
index dc3dffb..5cdf3c5 100644
--- a/drivers/mmc/bcm2835_sdhci.c
+++ b/drivers/mmc/bcm2835_sdhci.c
@@ -210,7 +210,7 @@
 	priv->last_write = 0;
 
 	host->name = dev->name;
-	host->ioaddr = (void *)base;
+	host->ioaddr = (void *)(uintptr_t)base;
 	host->quirks = SDHCI_QUIRK_BROKEN_VOLTAGE | SDHCI_QUIRK_BROKEN_R1B |
 		SDHCI_QUIRK_WAIT_SEND_CMD | SDHCI_QUIRK_NO_HISPD_BIT;
 	host->max_clk = emmc_freq;