IpClient: fix in InitialConfiguration validation.

This patch correctly invalidates InitialConfiguration objects with more
than one IPv4 address specified.

Bug: 111639419
Test: none
Change-Id: Ifda174636544311bee456f17946779bac7d4a49e

services/net/java/android/net/ip/IpClient.java

@@ -524,7 +524,7 @@ public class IpClient extends StateMachine {
                 return false;
             }
             // There no more than one IPv4 address
-            if (ipAddresses.stream().filter(Inet4Address.class::isInstance).count() > 1) {
+            if (ipAddresses.stream().filter(LinkAddress::isIPv4).count() > 1) {
                 return false;
             }