RFR [15/java.xml] 8242470 : Upgrade Xerces to Version 2.12.1

[Joe Wang]

Please review an update to Xerces 2.12.1. Xerces 2.12.1 was a bug fix 
release. Bugs in the release were either already in the JDK or not 
applicable. This patch therefore includes only an update to the md file.

--- a/src/java.xml/share/legal/xerces.md
+++ b/src/java.xml/share/legal/xerces.md
@@ -1,4 +1,4 @@
-## Apache Xerces v2.12.0
+## Apache Xerces v2.12.1

  ### Apache Xerces Notice
  <pre>
@@ -8,9 +8,11 @@
=========================================================================

      Apache Xerces Java
-    Copyright 1999-2018 The Apache Software Foundation
+    Copyright 1999-2020 The Apache Software Foundation
+
      This product includes software developed at
      The Apache Software Foundation (http://www.apache.org/).
+
      Portions of this software were originally based on the following:
      - software copyright (c) 1999, IBM Corporation., http://www.ibm.com.
      - software copyright (c) 1999, Sun Microsystems., http://www.sun.com.


Thanks,
Joe