install postfix-mysql only in debian platforms
install postfix-mysql only in debian platforms

onddo/postfix-dovecot-cookbook,RavenB/postfix-dovecot-cookbook,RavenB/postfix-dovecot-cookbook,ustuehler/postfix-dovecot-cookbook,zuazo/postfix-dovecot-cookbook,RavenB/postfix-dovecot-cookbook,zuazo/postfix-dovecot-cookbook,ustuehler/postfix-dovecot-cookbook,onddo/postfix-dovecot-cookbook,ustuehler/postfix-dovecot-cookbook,onddo/postfix-dovecot-cookbook