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>
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.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;
+    }
 }