bootstd: Add a bootdev command

Add a 'bootdev' command to handle listing and selection of bootdevs.

Disable standard boot for a few boards which otherwise run out of space.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 24e2ad7..5a48b84 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -700,6 +700,7 @@
 F:	boot/bootflow.c
 F:	boot/bootmeth*.c
 F:	boot/bootstd.c
+F:	cmd/bootdev.c
 F:	include/bootdev*.h
 F:	include/bootflow.h
 F:	include/bootmeth.h