move these forward declarations back to asterisk.h where they belong... even...

move these forward declarations back to asterisk.h where they belong... even though asterisk.h includes compat.h, these declarations have nothing to do with the being platform-compatible and are directly related to being part of Asterisk


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@89482 65c4cc65-6c06-0410-ace0-fbb531ad65f3