xend: Remove a couple of unused function prototypes.
xend: Remove a couple of unused function prototypes.

Commit 70f446631f142ae92b4d4eb349fcf11408171556 (from 2008) introduced
some functions for testing whether xend was returning correct sound
models.  Those functions have long gone, but the function prototypes
remain.  This commit removes the unused prototypes.

Signed-off-by: Richard W.M. Jones <d9c0c1814229c9d7f78a7e860ff9791c82a22dba@redhat.com>

olafhering/libvirt,fabianfreyer/libvirt,crobinso/libvirt,jardasgit/libvirt,datto/libvirt,datto/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,zippy2/libvirt,nertpinx/libvirt,nertpinx/libvirt,andreabolognani/libvirt,taget/libvirt,jardasgit/libvirt,eskultety/libvirt,VenkatDatta/libvirt,taget/libvirt,eskultety/libvirt,zippy2/libvirt,rlaager/libvirt,taget/libvirt,eskultety/libvirt,crobinso/libvirt,jardasgit/libvirt,nertpinx/libvirt,crobinso/libvirt,jfehlig/libvirt,rlaager/libvirt,libvirt/libvirt,datto/libvirt,rlaager/libvirt,jfehlig/libvirt,olafhering/libvirt,libvirt/libvirt,libvirt/libvirt,rlaager/libvirt,olafhering/libvirt,nertpinx/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,zippy2/libvirt,fabianfreyer/libvirt,agx/libvirt,agx/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,agx/libvirt,datto/libvirt,fabianfreyer/libvirt,libvirt/libvirt,VenkatDatta/libvirt,rlaager/libvirt,datto/libvirt,taget/libvirt,agx/libvirt,eskultety/libvirt,andreabolognani/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,agx/libvirt,zippy2/libvirt,eskultety/libvirt,jfehlig/libvirt,andreabolognani/libvirt,olafhering/libvirt,crobinso/libvirt,taget/libvirt,jfehlig/libvirt