mmc-utils: Support new ext_csd_rev in eMMC 5.1

The new eMMC 5.1 standard has ext_csd[192] (ext_csd_rev)
set to 8. This patch adds support to that.

BUG=None
TEST=Compiled

Change-Id: I588fa28ec966fc7746a1fa0cebf8bdc562d81b7a
Signed-off-by: Puthikorn Voravootivat <puthik@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/267776
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
diff --git a/mmc_cmds.c b/mmc_cmds.c
index 3ea1a61..5ec94c8 100644
--- a/mmc_cmds.c
+++ b/mmc_cmds.c
@@ -723,6 +723,7 @@
 		"4.41",	/* 5 */
 		"4.5",  /* 6 */
 		"5.0",  /* 7 */
+		"5.1",  /* 8 */
 	};
 	int boot_access;
 	const char* boot_access_str[] = {