NFS driver: Remove deprecated nfs_disk_util

The parameter was deprecated during the previous cycle[1] and has had
no effect since then.

[1] eb3361bc9981a6e3a50bc9ac9ec53f76bf140743

Change-Id: I3632a55f8f75873f1a9178bf42bac1f6c97d3c24

manifests/backend/nfs.pp

@@ -89,12 +89,6 @@
 #   Example :
 #     { 'nfs_backend/param1' => { 'value' => value1 } }
 #
-# DEPRECATED PARAMETERS
-#
-# [*nfs_disk_util*]
-#   (Optional) Use du or df for free space calculation.
-#   Defaults to undef
-#
 define cinder::backend::nfs (
   $volume_backend_name         = $name,
   $backend_availability_zone   = $::os_service_default,
@@ -112,18 +106,10 @@ define cinder::backend::nfs (
   $nfs_qcow2_volumes           = $::os_service_default,
   $manage_volume_type          = false,
   $extra_options               = {},
-  $nfs_disk_util               = undef,
 ) {
 
   include cinder::deps
 
-  if $nfs_disk_util != undef {
-    warning('The nfs_disk_util parameter is deprecated and has no effect.')
-  }
-  cinder_config {
-    "${name}/nfs_disk_util": ensure => absent
-  }
-
   file {$nfs_shares_config:
     content => join($nfs_servers, "\n"),
     require => Anchor['cinder::install::end'],

releasenotes/notes/remove-nfs_disk_util-78a168271a2dd7c7.yaml

@@ -0,0 +1,4 @@
+---
+upgrade:
+  - |
+    The ``cinder::backend::nfs::nfs_disk_util`` parameter has been removed.