Update year in copyright text to 2014

Change-Id: Ic7fb61aabae1d515b9e6baf3dd003807ff42da60
diff --git a/docs/porting-guide.md b/docs/porting-guide.md
index 11ff3cc..7b2e7d2 100644
--- a/docs/porting-guide.md
+++ b/docs/porting-guide.md
@@ -983,7 +983,7 @@
 
 - - - - - - - - - - - - - - - - - - - - - - - - - -
 
-_Copyright (c) 2013, ARM Limited and Contributors. All rights reserved._
+_Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved._
 
 
 [User Guide]: user-guide.md