[arch-dev-public] Perl 5.22 TODO clarification

I was just rebuilding perl-crypt-openssl-bignum and noticed that the template did not work as expected. Please make sure the package function is defined with {} rather than () for the code block. It looks like some perl package generation script might have used (). Also if perl is only an optdep of your package you should not include the template as that will make it a hard dep.