MMC: Do not set unsupported bits in OCR response

The card might go to inactive state (according to specification), if
there are unsupported bits set in the OCR.

Signed-off-by: Timo Teras <timo.teras@solidboot.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index ec8168a..766bc544 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -475,7 +475,7 @@
 	if (bit) {
 		bit -= 1;
 
-		ocr = 3 << bit;
+		ocr &= 3 << bit;
 
 		host->ios.vdd = bit;
 		mmc_set_ios(host);