Add a local perl module to get year last changed

Add a local perl module to get year last changed

This is used for generating a more-correct copyright statement
for the "build_generated" targets.

Fixes: #13765
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/13791)