fix crash when transcoder processes a 200Ok with a SDP offer incompatible.
fix crash when transcoder processes a 200Ok with a SDP offer incompatible.

biddyweb/flexisip,biddyweb/flexisip,biddyweb/flexisip,gale320/flexisip,BelledonneCommunications/flexisip,BelledonneCommunications/flexisip,BelledonneCommunications/flexisip,BelledonneCommunications/flexisip,biddyweb/flexisip,gale320/flexisip,gale320/flexisip,gale320/flexisip