build: use proper pod for nested bulleted VIRSH_DEBUG list
build: use proper pod for nested bulleted VIRSH_DEBUG list

Newer pod (hello rawhide) complains if you attempt to mix bullets
and non-bullets in the same list:

virsh.pod around line 3177: Expected text after =item, not a bullet

As our intent was to nest an inner list, we make that explicit to
keep pod happy.

* tools/virsh.pod (ENVIRONMENT): Use correct pod syntax.

olafhering/libvirt,zhlcindy/libvirt-1.1.4-maintain,olafhering/libvirt,zippy2/libvirt,nertpinx/libvirt,agx/libvirt,fabianfreyer/libvirt,VenkatDatta/libvirt,datto/libvirt,andreabolognani/libvirt,crobinso/libvirt,cbosdo/libvirt,eskultety/libvirt,libvirt/libvirt,nertpinx/libvirt,andreabolognani/libvirt,jardasgit/libvirt,rlaager/libvirt,nertpinx/libvirt,elmarco/libvirt,zippy2/libvirt,shugaoye/libvirt,datto/libvirt,cbosdo/libvirt,zhlcindy/libvirt-1.1.4-maintain,rlaager/libvirt,nertpinx/libvirt,elmarco/libvirt,cbosdo/libvirt,cbosdo/libvirt,elmarco/libvirt,zippy2/libvirt,crobinso/libvirt,VenkatDatta/libvirt,eskultety/libvirt,zippy2/libvirt,nertpinx/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,rlaager/libvirt,libvirt/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,cbosdo/libvirt,VenkatDatta/libvirt,rlaager/libvirt,zhlcindy/libvirt-1.1.4-maintain,taget/libvirt,eskultety/libvirt,olafhering/libvirt,taget/libvirt,shugaoye/libvirt,eskultety/libvirt,libvirt/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,jfehlig/libvirt,eskultety/libvirt,agx/libvirt,elmarco/libvirt,zhlcindy/libvirt-1.1.4-maintain,jfehlig/libvirt,andreabolognani/libvirt,crobinso/libvirt,jardasgit/libvirt,taget/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,zhlcindy/libvirt-1.1.4-maintain,datto/libvirt,shugaoye/libvirt,crobinso/libvirt,agx/libvirt,elmarco/libvirt,datto/libvirt,agx/libvirt,shugaoye/libvirt,taget/libvirt,andreabolognani/libvirt,libvirt/libvirt,datto/libvirt,olafhering/libvirt,jardasgit/libvirt,taget/libvirt,agx/libvirt,shugaoye/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,rlaager/libvirt