Fix for lvm_filters in case if storage.lvm is not defined.

- lvm_filters are not managed if no lvm pillar is in place.
  One should be able to manage lvm_filters without managing lvm
  items.

Prod-Related: PROD-36201
Change-Id: Ibef8244f27ffea6f7babced5634ed2b287eb8304
diff --git a/README.rst b/README.rst
index 03dc3d5..4d66e8a 100644
--- a/README.rst
+++ b/README.rst
@@ -2485,6 +2485,7 @@
     parameters:
       linux:
         storage:
+          enabled: true
           mount:
             data:
               enabled: true