Change version number to 2.2.1

Changed version for library files and yotta module
diff --git a/doxygen/input/doc_mainpage.h b/doxygen/input/doc_mainpage.h
index 35131ce..9643a6f 100644
--- a/doxygen/input/doc_mainpage.h
+++ b/doxygen/input/doc_mainpage.h
@@ -21,7 +21,7 @@
  */
 
 /**
- * @mainpage mbed TLS v2.2.0 source code documentation
+ * @mainpage mbed TLS v2.2.1 source code documentation
  *
  * This documentation describes the internal structure of mbed TLS.  It was
  * automatically generated from specially formatted comment blocks in