expo: Add a configuration editor

Add a new 'cedit' command which allows editing configuration using an
expo. The configuration items appear as menus on the display.

This is extremely basic, only supporting menus and not providing any way
to load or save the configuration.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/cmd/Kconfig b/cmd/Kconfig
index c194184..f6b10e0 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -428,6 +428,15 @@
 
 	  See doc/android/boot-image.rst for details.
 
+config CMD_CEDIT
+	bool "cedit - Configuration editor"
+	depends on CEDIT
+	default y
+	help
+	  Provides a command to allow editing of board configuration and
+	  providing a UI for the user to adjust settings. Subcommands allow
+	  loading and saving of configuration as well as showing an editor.
+
 config CMD_ELF
 	bool "bootelf, bootvx"
 	default y