[exim] 4.70 freebsd pwcheck

not obvious to me how to config 4.70 on freebsd to compile with

    CYRUS_PWCHECK_SOCKET=/var/pwcheck/pwcheck

yes, i know this is not the wonderful way to do things :)

    [X] AUTH_SASL          Enable use of Cyrus SASL auth library 

does not do it

randy