* nua_dialog.h: added NUA_DIALOG_USAGE_PRIVATE() and NUA_DIALOG_USAGE_PUBLIC()
  
  Macros to use with non-NULL pointers.



git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@8605 d0543943-73ff-0310-b7d9-9358b9ac24b2