Don't duplicate function if not needed...

- removing transmit_reinvite_with_t38_sdp in favour of adding an argument to 
  transmit_reinvite_with_sdp


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@46385 65c4cc65-6c06-0410-ace0-fbb531ad65f3