mmc: core: Extend sysfs with OCR register

Registers CID and CSD are already exported through sysfs so let's make
this interface complete by adding missing OCR register.

Signed-off-by: Bojan Prtvar <prtvar.b@gmail.com>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 5485040..403b97b 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -749,6 +749,7 @@
 MMC_DEV_ATTR(enhanced_area_size, "%u\n", card->ext_csd.enhanced_area_size);
 MMC_DEV_ATTR(raw_rpmb_size_mult, "%#x\n", card->ext_csd.raw_rpmb_size_mult);
 MMC_DEV_ATTR(rel_sectors, "%#x\n", card->ext_csd.rel_sectors);
+MMC_DEV_ATTR(ocr, "%08x\n", card->ocr);
 
 static ssize_t mmc_fwrev_show(struct device *dev,
 			      struct device_attribute *attr,
@@ -784,6 +785,7 @@
 	&dev_attr_enhanced_area_size.attr,
 	&dev_attr_raw_rpmb_size_mult.attr,
 	&dev_attr_rel_sectors.attr,
+	&dev_attr_ocr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(mmc_std);