common, autoboot: sync functionality with Kconfig description

add back again special case: -2
autoboot with no delay and no check for abort

as described in Kconfig option, see common/Kconfig
help text for option BOOTDELAY.

Signed-off-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
1 file changed