Remove libssl linking

[beelzetron]

Hi Andres, i am the fedora libshairport package maintainer, i am proposing you this change to configure.in because it seems that libssl is actually linked but not used. Fedora packaging guidelines impose me to remove unused linked libraries. If libssl needs to be linked, just let me know so i can report to my fedora reviewer and go ahead with review process. This is the fedora bug opened to package your libshairport code and allow xbmc to be built with airtunes/airplay support on fedora too.

Thank you, Lorenzo