Update to kernel headers v4.12.3.

Test: Built angler.
Change-Id: Icbcf4fac2334de8409b049ed7a3b4c24b4e98ce9
diff --git a/libc/kernel/uapi/linux/llc.h b/libc/kernel/uapi/linux/llc.h
index 41c4d84..e6f778f 100644
--- a/libc/kernel/uapi/linux/llc.h
+++ b/libc/kernel/uapi/linux/llc.h
@@ -19,6 +19,7 @@
 #ifndef _UAPI__LINUX_LLC_H
 #define _UAPI__LINUX_LLC_H
 #include <linux/socket.h>
+#include <linux/if.h>
 #define __LLC_SOCK_SIZE__ 16
 struct sockaddr_llc {
   __kernel_sa_family_t sllc_family;