Add NotNull and Argument check during object build for LISP object

Also correct IP enumeration type into IP4.

Change-Id: Id970ee608c885826cfd2de7b5448b2bc451e079f
diff --git a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/AddressFamilyIdentifierEnum.java b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/AddressFamilyIdentifierEnum.java
index 526c8b4..e1a4d97 100644
--- a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/AddressFamilyIdentifierEnum.java
+++ b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/AddressFamilyIdentifierEnum.java
@@ -26,7 +26,7 @@
 public enum AddressFamilyIdentifierEnum {
 
     NO_ADDRESS(0),              // Reserved
-    IP(1),                      // IP (IP version 4)
+    IP4(1),                     // IP4 (IP version 4)
     IP6(2),                     // IP6 (IP version 6)
     DNS(16),                    // Domain Name System
     DISTINGUISHED_NAME(17),     // Distinguished Name