Update to kernel headers to v5.1.3.

Test: Builds and boots taimen.
Test: Ran bionic unit tests.
Change-Id: Ieaca8709d568f075df8cac60c9da2c0ed1916963
diff --git a/libc/kernel/uapi/linux/in.h b/libc/kernel/uapi/linux/in.h
index 9ed00b4..f1dab00 100644
--- a/libc/kernel/uapi/linux/in.h
+++ b/libc/kernel/uapi/linux/in.h
@@ -215,6 +215,7 @@
 #define INADDR_UNSPEC_GROUP 0xe0000000U
 #define INADDR_ALLHOSTS_GROUP 0xe0000001U
 #define INADDR_ALLRTRS_GROUP 0xe0000002U
+#define INADDR_ALLSNOOPERS_GROUP 0xe000006aU
 #define INADDR_MAX_LOCAL_GROUP 0xe00000ffU
 #endif
 #include <asm/byteorder.h>