storage: gluster: Implement 'checkPool' method so that state is restored
storage: gluster: Implement 'checkPool' method so that state is restored

After restart of libvirtd the 'checkPool' method is supposed to validate
that the pool is online. Since libvirt then refreshes the pool contents
anyways just return whether the pool was supposed to be online so that
the code can be reached. This is necessary since if a pool does not
implement the method it's automatically considered as inactive.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1436065

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