Add a bootretry_ prefix to these two functions, and remove the need for
the #ifdef around everything (it moves to the Makefile).
Signed-off-by: Simon Glass <sjg@chromium.org>
This code is only used by one board, so it seems a shame to clutter up
the readline code with it. Move it into its own file.
Signed-off-by: Simon Glass <sjg@chromium.org>