If the cluster name and state are stored on NFS (with root_squash),

trying to verify the cluster name (which may try to /create/ files or
directories) *before* dropping privs results in a fatal error as
slurmctld tries to create items which ultimately fail.  Moving
this process until after the privs and uid have changed allows
the process to succeed.

Reported by Jon Nelson <jdnelson@dyn.com>

Bug 2728