I do not have access to a mysql instance with tls/ssl right now, but I remember using this instructions and getting it to work:

http://linux.uits.uconn.edu/2013/04/30/setting-up-mysql-over-tls/

You need first to set the certificate settings in your mysql client settings (systemwide /etc/my.cnf, user in ~/.my.cnf); after that you can add mysql_ssl=1 to the db handle in your perl script.