rpm: fix /var/lib/libvirt permissions

rpm: fix /var/lib/libvirt permissions

https://bugzilla.redhat.com/show_bug.cgi?id=649511

Regression of forcing 0700 permissions (which breaks guest startup
because the qemu user can't see /var/lib/libvirt/*.monitor) was
introduced in commit 66823690e, as part of libvirt 0.8.2.

* libvirt.spec.in (%files): Drop %{_localstatedir}/lib/libvirt,
since libvirt depends on libvirt-client.
(%files client): Guarantee 755 permissions on
%(_localstatedir}/lib/libvirt, since the qemu user must be able to
do pathname resolution to a subdirectory.