Add flexible management of lvm filters

Allow user to flexibly manage filters in lvm.conf via
linux:storage:lvm_filters dictionary

Change-Id: I37928610f0ec2bd3ef6f5eac2e5d555a0ce39aa2
Related-Prod: PROD-26396
(cherry picked from commit 40bb5e7efd03e98606c06abf8a55a0e47bf7dab9)
diff --git a/README.rst b/README.rst
index cdbfeae..4efa5e2 100644
--- a/README.rst
+++ b/README.rst
@@ -2106,6 +2106,20 @@
                 data:
                   size: 40G
                   mount: ${linux:storage:mount:data}
+          # When set they will take precedence over filters aget from volume groups.
+          lvm_filters:
+            10:
+              enabled: True
+              value: "a|loop|"
+            20:
+              enabled: True
+              value: "r|/dev/hdc|"
+            30:
+              enabled: True
+              value: "a|/dev/ide|"
+            40:
+              enabled: True
+              value: "r|.*|"
 
 Create partitions on disk. Specify size in MB. It expects empty
 disk without any existing partitions.