Add DHCPv6 IA_PD and IA_PREFIX option constants.

Bug: 260934173
Test: m
Change-Id: I2f6692f4915c937787f023d40924f17f61d4a44e
diff --git a/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java b/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
index 7b3943c..1d88d6e 100644
--- a/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
+++ b/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
@@ -214,11 +214,14 @@
      *
      * See also:
      *     - https://datatracker.ietf.org/doc/html/rfc8415
+     *     - https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml
      */
     public static final int DHCP6_CLIENT_PORT = 546;
     public static final int DHCP6_SERVER_PORT = 547;
     public static final Inet6Address ALL_DHCP_RELAY_AGENTS_AND_SERVERS =
             (Inet6Address) InetAddresses.parseNumericAddress("ff02::1:2");
+    public static final int DHCP6_OPTION_IA_PD = 25;
+    public static final int DHCP6_OPTION_IAPREFIX = 26;
 
     /**
      * IEEE802.11 standard constants.