lib/List/MoreUtils.pm: improve loading XS module
lib/List/MoreUtils.pm: improve loading XS module

Import functions either from separately installed XS module or from bundled PP
version.

Signed-off-by: Jens Rehsack <69d49c504a9219a55b8be0f905e8fe3c32ffb57f@netbsd.org>

perl5-utils/List-MoreUtils