Deprecate Ipv6Address::IsAllHostsMulticast()

RELEASE_NOTES

@@ -34,6 +34,8 @@ New user-visible features
 - (internet) L4 protocols (e.g., TCP, UDP, ICMP, etc.) can be demultiplexed by IP
   according to the incoming interface. In other words, it is now possible to
   use specialized L4 protocols according to the interface.
+- (internet) Ipv6Address::IsAllHostsMulticast() is now deprecated. FF02::3 is not
+  in the official reserved IPv6 multicast address list.
 
 Bugs fixed
 ----------

src/network/utils/ipv6-address.h

@@ -29,6 +29,7 @@
 #include "ns3/attribute-helper.h"
 #include "ns3/address.h"
 #include "ns3/ipv4-address.h"
+#include "ns3/deprecated.h"
 
 namespace ns3 { 
 
@@ -223,9 +224,12 @@ public:
 
   /**
    * \brief If the IPv6 address is "all hosts multicast" (ff02::3/8).
+   *
+   * This function is deprecated because the address has been removed from RFCs.
+   *
    * \return true if "all hosts multicast", false otherwise
    */
-  bool IsAllHostsMulticast () const;
+  bool IsAllHostsMulticast () const NS_DEPRECATED;
 
   /**
    * \brief If the IPv6 address is a link-local address (fe80::/64).