arm: fix CONFIG_DELAY_ENVIRONMENT to act like it claims in the README

No one expects to end up in a delayed environment if
CONFIG_DELAY_ENVIRONMENT isn't defined.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Acked-by: Simon Glass <sjg@chromium.org>
Acked-by: Allen Martin <amartin@nvidia.com>