image: Add fallback for fit_config_verify

Add a fallback for this function so it can be used without regard to
whether FIT_SIGNATURE is enabled or not.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
1 file changed