fix compiling warning

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2052 bbd45198-f89e-11dd-88c7-29a3b14d5316

components/drivers/sdio/mmcsd_core.c

@@ -175,7 +175,7 @@ rt_int32_t mmcsd_get_cid(struct rt_mmcsd_host *host, rt_uint32_t *cid)
 		return 0;
 	}
 
-	buf = (rt_uint8_t *)rt_malloc(16);
+	buf = (rt_uint32_t *)rt_malloc(16);
 	if (!buf) 
 	{
 		rt_kprintf("allocate memory failed\n");
@@ -248,7 +248,7 @@ rt_int32_t mmcsd_get_csd(struct rt_mmcsd_card *card, rt_uint32_t *csd)
 		return 0;
 	}
 
-	buf = (rt_uint8_t*)rt_malloc(16);
+	buf = (rt_uint32_t*)rt_malloc(16);
 	if (!buf) 
 	{
 		rt_kprintf("allocate memory failed\n");