Update to kernel headers v4.12.3.

Test: Built angler.
Change-Id: Icbcf4fac2334de8409b049ed7a3b4c24b4e98ce9
diff --git a/libc/kernel/uapi/linux/gtp.h b/libc/kernel/uapi/linux/gtp.h
index 780f500..bd2fbcb 100644
--- a/libc/kernel/uapi/linux/gtp.h
+++ b/libc/kernel/uapi/linux/gtp.h
@@ -33,7 +33,8 @@
   GTPA_LINK,
   GTPA_VERSION,
   GTPA_TID,
-  GTPA_SGSN_ADDRESS,
+  GTPA_PEER_ADDRESS,
+#define GTPA_SGSN_ADDRESS GTPA_PEER_ADDRESS
   GTPA_MS_ADDRESS,
   GTPA_FLOW,
   GTPA_NET_NS_FD,