setup.cfg: Cleanup

- pbr hasn't need the hook configuration since forever [1]

[1] https://github.com/openstack/pbr/commit/c84876dc0f559a66fec19b2f81f5717204b253e2

Change-Id: If14fab7d7997f1a324cd3335d627868de3fafd8a

setup.cfg

@@ -44,10 +44,6 @@ console_scripts =
     kolla-genpwd = kolla_ansible.cmd.genpwd:main
     kolla-mergepwd = kolla_ansible.cmd.mergepwd:main
 
-[global]
-setup-hooks =
-    pbr.hooks.setup_hook
-
 [build_releasenotes]
 all_files = 1
 build-dir = releasenotes/build