Convert CONFIG_CMD_DEKBLOB to Kconfig

This converts the following to Kconfig:
   CONFIG_CMD_DEKBLOB

Note: This option does not seem to actually be enabled by any board.

Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: imply under SECURE_BOOT for mx5/6/7]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/imx-common/Kconfig b/arch/arm/imx-common/Kconfig
index 5eb3ba0..25cbd12 100644
--- a/arch/arm/imx-common/Kconfig
+++ b/arch/arm/imx-common/Kconfig
@@ -29,6 +29,7 @@
 	bool "Support i.MX HAB features"
 	depends on ARCH_MX7 || ARCH_MX6 || ARCH_MX5
 	select FSL_CAAM
+	imply CMD_DEKBLOB
 	help
 	  This option enables the support for secure boot (HAB).
 	  See doc/README.mxc_hab for more details.
@@ -46,3 +47,11 @@
 	  on U-Boot.  Using the reset button or running bmode normal
 	  will set it back to normal.  This command currently
 	  supports i.MX53 and i.MX6.
+
+config CMD_DEKBLOB
+	bool "Support the 'dek_blob' command"
+	help
+	  This enables the 'dek_blob' command which is used with the
+	  Freescale secure boot mechanism. This command encapsulates and
+	  creates a blob of data. See also CMD_BLOB and doc/README.mxc_hab for
+	  more information.