spl: crypto: fix including SHA* object files in SPL

If one of SHA* algorithms is disabled in u-boot, its code is not
included in SPL even if a given SHA* option is enabled in SPL. Fix
this.

Fixes: 603d15a5 ("spl: cypto: Bring back SPL_ versions of SHA")
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@foundries.io>
Reviewed-by: Tom Rini <trini@konsulko.com>