FreeSWITCH-mod-radius-cdr_improvement

push prefix dir from configure instead of from the makefile to clean up the compile line a bit.  Follow-up commit of autotools, please hold.

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@4508 d0543943-73ff-0310-b7d9-9358b9ac24b2