libxl: remove obsolete check for xend during driver startup
libxl: remove obsolete check for xend during driver startup

No supported build targets for libvirt still ship xend, so there is no
need for the libxl driver to check for it anymore.

Signed-off-by: Daniel P. Berrangé <bb938cf255e055ff3507f2627d214e8e62118fcf@redhat.com>

andreabolognani/libvirt,jfehlig/libvirt,libvirt/libvirt,andreabolognani/libvirt,zippy2/libvirt,eskultety/libvirt,jardasgit/libvirt,nertpinx/libvirt,jfehlig/libvirt,nertpinx/libvirt,andreabolognani/libvirt,eskultety/libvirt,jfehlig/libvirt,jardasgit/libvirt,eskultety/libvirt,olafhering/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,andreabolognani/libvirt,jardasgit/libvirt,libvirt/libvirt,crobinso/libvirt,zippy2/libvirt,nertpinx/libvirt,eskultety/libvirt,fabianfreyer/libvirt,andreabolognani/libvirt,zippy2/libvirt,crobinso/libvirt,eskultety/libvirt,zippy2/libvirt,jardasgit/libvirt,crobinso/libvirt,libvirt/libvirt,jfehlig/libvirt,libvirt/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,crobinso/libvirt,olafhering/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,olafhering/libvirt,fabianfreyer/libvirt,olafhering/libvirt