Backport upstream perl 64bit hash alignment fixes

Backport upstream perl 64bit hash alignment fixes

Different flags triggering new compiler optimizations means that
luck has run out on this working by chance with the strict alignment
of octeon.

Upstream issue:
https://github.com/Perl/perl5/issues/18555

This is a combination of three commits from upstream.
https://github.com/Perl/perl5/commit/d18575f18c6ee61ce80492e82cae7361358d570a
https://github.com/Perl/perl5/commit/6027b190154088fbbcbde08a80c49531e4e4c012
https://github.com/Perl/perl5/commit/f43079cb514e3d0be0036424695438ae3fb58451

works on all arch deraadt@