s/copyright char/(C)/g to make compiler happy

Compiler complaining about the copyright characters.

Change-Id: I6730a50a668899a33e9dfcc4accb67ee207a3f08
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/filedescriptor.cpp b/filedescriptor.cpp
index 6a4b898..89f77e2 100644
--- a/filedescriptor.cpp
+++ b/filedescriptor.cpp
@@ -1,5 +1,5 @@
 /**
- * Copyright © 2017 IBM Corporation
+ * Copyright (C) 2017 IBM Corporation
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.