community/zoneminder: Added perl-json-maybexs to depends

Avoid zmtelemetry.pl to fail with the following message:

Can't locate JSON/MaybeXS.pm in @INC (you may need to install the JSON::MaybeXS module) (@INC contains: /usr/local/lib/perl5/site_perl /usr/local/share/perl5/site_perl /usr/lib/perl5/vendor_perl /usr/share/perl5/vendor_perl /usr/lib/perl5/core_perl /usr/share/perl5/core_perl) at /usr/bin/zmtelemetry.pl line 37.