fix printing ENH_START_ADDR

The enhanced user area start field is 4 bytes long
according to the eMMC 4.41 spec.

Signed-off-by: Ben Gardiner <bengardiner@nanometrics.ca>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/mmc.h b/mmc.h
index c6fcc83..491ce0a 100644
--- a/mmc.h
+++ b/mmc.h
@@ -47,6 +47,10 @@
 #define EXT_CSD_RST_N_FUNCTION		162	/* R/W */
 #define EXT_CSD_PARTITIONING_SUPPORT	160	/* RO */
 #define EXT_CSD_PARTITION_SETTING_COMPLETED	155	/* R/W */
+#define EXT_CSD_ENH_START_ADDR_3	139
+#define EXT_CSD_ENH_START_ADDR_2	138
+#define EXT_CSD_ENH_START_ADDR_1	137
+#define EXT_CSD_ENH_START_ADDR_0	136
 #define EXT_CSD_NATIVE_SECTOR_SIZE	63 /* R */
 #define EXT_CSD_USE_NATIVE_SECTOR	62 /* R/W */
 #define EXT_CSD_DATA_SECTOR_SIZE	61 /* R */