Feature 10936 Keeping persistent volume of VNF

Adding keep-volume key to the description of vdu-storage-requirements

Change-Id: I750e4b4b3979ad61220bf06310770c90108f2986
Signed-off-by: Gulsum Atici <gulsum.atici@canonical.com>
diff --git a/models/augments/additional-info.yang b/models/augments/additional-info.yang
index 2119073..6b460c1 100644
--- a/models/augments/additional-info.yang
+++ b/models/augments/additional-info.yang
@@ -39,4 +39,8 @@
     augment "/vnfd:vnfd/vnfd:virtual-storage-desc" {
         uses common:description;
     }
+
+    augment "/vnfd:vnfd/vnfd:virtual-storage-desc/vnfd:vdu-storage-requirements" {
+        uses common:vdu-storage-requirements;
+    }
 }
diff --git a/models/augments/common-augments.yang b/models/augments/common-augments.yang
index f1235eb..cf883b9 100644
--- a/models/augments/common-augments.yang
+++ b/models/augments/common-augments.yang
@@ -726,6 +726,27 @@
         }
     }
 
+    grouping vdu-storage-requirements {
+        list vdu-storage-requirements {
+            description
+              "Array of key-value pairs that articulate the storage
+               deployment requirements. If the storage type is persistent-storage
+               following setting holds the persistent volume upon VM deletion:
+               key: keep-volume
+               value: true";
+
+            key "key";
+
+            leaf key {
+                type string;
+            }
+
+            leaf value {
+                type string;
+            }
+        }
+    }
+
     typedef scaling-trigger {
         type enumeration {
             enum pre-scale-in {