Fix some compilation problems in app_voicemail. There was a parenthesis missing

in a function prototype, and "#elifdef" is not a valid preprocessor directive.
(issue #9122, akohlsmith)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@56187 65c4cc65-6c06-0410-ace0-fbb531ad65f3