Update kernel headers to v3.18.3.

Bug: 19127803
Change-Id: I67fa0832322ddd0032d909476047578be052bcf2
diff --git a/libc/kernel/uapi/linux/random.h b/libc/kernel/uapi/linux/random.h
index 6215d08..c81559c 100644
--- a/libc/kernel/uapi/linux/random.h
+++ b/libc/kernel/uapi/linux/random.h
@@ -36,4 +36,6 @@
  __u32 buf[0];
 };
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+#define GRND_NONBLOCK 0x0001
+#define GRND_RANDOM 0x0002
 #endif