uboot-phytec

sandbox: Allow return from board_init_f()

The execution flow becomes easier if we can return from board_init_f()
as ARM does. We can control things from start.c instead of having to
call back into that file from other places.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>