security/libxcrypt: Use upstream release archive and improve port

• Use upstream release tarball, removed USES= autoreconf dependency
• Remove patch, not necessary
• Add Perl5 build dependency
• Use INSTALL_TARGET instead of post-install for stripping
• Remove "make test" info, this shouldn't go into the port Makefile

PR: 290822
Approved by: maintainer timeout, 1+ month