slapd fails to start on boot due to /var/run/openldap/ missing

Issue

• slapd appears to fail to start every boot.

<root@localhost:~># systemctl status slapd -l
● slapd.service - OpenLDAP Server Daemon
   Loaded: loaded (/usr/lib/systemd/system/slapd.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since Mon 2018-06-11 11:43:48 EDT; 41min ago
     Docs: man:slapd
           man:slapd-config
           man:slapd-hdb
           man:slapd-mdb
           file:///usr/share/doc/openldap-servers/guide.html
  Process: 1270 ExecStart=/usr/sbin/slapd -u ldap -h ${SLAPD_URLS} $SLAPD_OPTIONS (code=exited, status=1/FAILURE)
  Process: 1195 ExecStartPre=/usr/libexec/openldap/check-config.sh (code=exited, status=0/SUCCESS)

Jun 11 11:43:48 localhost runuser[1261]: pam_unix(runuser:session): session closed for user ldap
Jun 11 11:43:48 localhost runuser[1267]: pam_unix(runuser:session): session opened for user ldap by (uid=0)
Jun 11 11:43:48 localhost slapd[1270]: @(#) $OpenLDAP: slapd 2.4.44 (Apr  3 2018 08:03:36) $
                                                  mockbuild@x86-034.build.eng.bos.redhat.com:/builddir/build/BUILD/openldap-2.4.44/openldap-2.4.44/servers/slapd
Jun 11 11:43:48 localhost slapd[1308]: unable to open pid file "/var/run/openldap/slapd.pid": 2 (No such file or directory)
Jun 11 11:43:48 localhost slapd[1308]: slapd stopped.
Jun 11 11:43:48 localhost slapd[1308]: connections_destroy: nothing to destroy.
Jun 11 11:43:48 localhost systemd[1]: slapd.service: control process exited, code=exited status=1
Jun 11 11:43:48 localhost systemd[1]: Failed to start OpenLDAP Server Daemon.
Jun 11 11:43:48 localhost systemd[1]: Unit slapd.service entered failed state.
Jun 11 11:43:48 localhost systemd[1]: slapd.service failed.
<root@localhost:~>#