handle_speechset has 4 arguments.

Update code to reflect that handle_speechset has 4 arguments.

(closes issue #17093)
Reported by: gpatri
Patches: 
      res_agi.patch uploaded by gpatri (license 1014)
Tested by: pabelanger, mmichelson

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@254446 65c4cc65-6c06-0410-ace0-fbb531ad65f3