* sdp_print(): correctly handle NULL session
  Ignore-this: 206a9027d6dfb73371d7f0ddac5f640b
  
  Coverity issue.


git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@13342 d0543943-73ff-0310-b7d9-9358b9ac24b2