mmc: add missing printk levels

Some printk:s were missing an explicit level.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

drivers/mmc/core/mmc.c

@@ -212,8 +212,9 @@ static int mmc_read_ext_csd(struct mmc_card *card)
 
 	ext_csd_struct = ext_csd[EXT_CSD_REV];
 	if (ext_csd_struct > 2) {
-		printk("%s: unrecognised EXT_CSD structure version %d\n",
-			mmc_hostname(card->host), ext_csd_struct);
+		printk(KERN_ERR "%s: unrecognised EXT_CSD structure "
+			"version %d\n", mmc_hostname(card->host),
+			ext_csd_struct);
 		return -EINVAL;
 	}