Update to kernel headers v4.7.2.

Modify the kernel header update script to rename C++ keyword
struct members to something else. This fixes problems when including
these kernel files in C++ code.

Also, make a manual change to linux/fib_rules.h and comment out the
value FRA_PAD since it conflicts with a special android kernel value
FRA_UID_START that has not been upstreamed yet.

Test: Built aosp_angler, aosp_x86_64, aosp_mips (bionic only)
Test: Booted on angler and ran bionic unit tests
Test: Built these changes in internal master

Change-Id: Ia22b7e3ca409404696dba76311f49157f4a9ceed
diff --git a/libc/kernel/uapi/linux/ipv6.h b/libc/kernel/uapi/linux/ipv6.h
index 24d5743..5a1d4fd 100644
--- a/libc/kernel/uapi/linux/ipv6.h
+++ b/libc/kernel/uapi/linux/ipv6.h
@@ -157,7 +157,10 @@
   DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT,
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
   DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN,
+  DEVCONF_DROP_UNICAST_IN_L2_MULTICAST,
+  DEVCONF_DROP_UNSOLICITED_NA,
+  DEVCONF_KEEP_ADDR_ON_DOWN,
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
   DEVCONF_MAX
 };
 #endif
-/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */