update exfat from current head

Change-Id: I7d93474296612fda1dde23f6e8690668d6880e27
diff --git a/exfat/libexfat/compiler.h b/exfat/libexfat/compiler.h
index 6edd8ec..473726d 100644
--- a/exfat/libexfat/compiler.h
+++ b/exfat/libexfat/compiler.h
@@ -4,7 +4,7 @@
 	showstopper.
 
 	Free exFAT implementation.
-	Copyright (C) 2010-2013  Andrew Nayenko
+	Copyright (C) 2010-2014  Andrew Nayenko
 
 	This program is free software; you can redistribute it and/or modify
 	it under the terms of the GNU General Public License as published by
@@ -24,6 +24,12 @@
 #ifndef COMPILER_H_INCLUDED
 #define COMPILER_H_INCLUDED
 
+/*
+#if __STDC_VERSION__ < 199901L
+#error C99-compliant compiler is required
+#endif
+*/
+
 #if defined(__clang__)
 
 #define PRINTF __attribute__((format(printf, 1, 2)))