at91_mci: Fix bad reference

The flags parameter got removed in a previous commit, but some
references were overlooked.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/host/au1xmmc.c b/drivers/mmc/host/au1xmmc.c
index c77fadc..b2104d4 100644
--- a/drivers/mmc/host/au1xmmc.c
+++ b/drivers/mmc/host/au1xmmc.c
@@ -212,12 +212,12 @@
 	}
 
 	if (data) {
-		if (flags & MMC_DATA_READ) {
+		if (data->flags & MMC_DATA_READ) {
 			if (data->blocks > 1)
 				mmccmd |= SD_CMD_CT_4;
 			else
 				mmccmd |= SD_CMD_CT_2;
-		} else if (flags & MMC_DATA_WRITE) {
+		} else if (data->flags & MMC_DATA_WRITE) {
 			if (data->blocks > 1)
 				mmccmd |= SD_CMD_CT_3;
 			else