OS-2366 ddi_periodic_add(9F) is entirely rubbish

*** 19,29 ****
   * CDDL HEADER END
   */
  /*
   * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
   * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2012 Joyent, Inc. All rights reserved.
   */
  
  #include <mdb/mdb_param.h>
  #include <mdb/mdb_modapi.h>
  #include <mdb/mdb_ks.h>
--- 19,29 ----
   * CDDL HEADER END
   */
  /*
   * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
   * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2013 Joyent, Inc. All rights reserved.
   */
  
  #include <mdb/mdb_param.h>
  #include <mdb/mdb_modapi.h>
  #include <mdb/mdb_ks.h>
*** 69,78 ****
--- 69,79 ----
  #include "cpupart_mdb.h"
  #include "cred.h"
  #include "ctxop.h"
  #include "cyclic.h"
  #include "damap.h"
+ #include "ddi_periodic.h"
  #include "devinfo.h"
  #include "findstack.h"
  #include "fm.h"
  #include "group.h"
  #include "irm.h"
*** 3880,3889 ****
--- 3881,3893 ----
          { "cyctrace", "?", "dump cyclic trace buffer", cyctrace },
  
          /* from damap.c */
          { "damap", ":", "display a damap_t", damap, damap_help },
  
+         /* from ddi_periodic.c */
+         { "ddi_periodic", "?[-v]", "dump ddi_periodic_impl_t info", dprinfo },
+ 
          /* from devinfo.c */
          { "devbindings", "?[-qs] [device-name | major-num]",
              "print devinfo nodes bound to device-name or major-num",
              devbindings, devinfo_help },
          { "devinfo", ":[-qs]", "detailed devinfo of one node", devinfo,