Fix out of bounds access.

key.first is a pointer, so we shouldn't use the & operator here.
CID 610870 and 610871.
Should also fix ticket #9184. At least I cannot reproduce it anymore.

src/add-ons/kernel/network/protocols/ipv6/ipv6.cpp

@@ -501,7 +501,7 @@ size_t
 MulticastStateHash::HashKey(const KeyType &key) const
 {
 	size_t result = 0;
-	result = jenkins_hashword((const uint32*)&key.first,
+	result = jenkins_hashword((const uint32*)key.first,
 		sizeof(in6_addr) / sizeof(uint32), result);
 	result = jenkins_hashword(&key.second, 1, result);
 	return result;

src/add-ons/kernel/network/protocols/ipv6/multicast.h

@@ -172,7 +172,7 @@ public:
 		size_t HashKey(const KeyType &key) const
 			{
 				size_t result = 0;
-				result = jenkins_hashword((const uint32*)&key.first, 
+				result = jenkins_hashword((const uint32*)key.first,
 					sizeof(in6_addr) / sizeof(uint32), result);
 				result = jenkins_hashword(&key.second, 1, result);
 				return result;