Update to NSPR 4.9.5, part 1: MPL 2 upgrade only.

mozilla/nsprpub/pr/src/md/unix/os_Linux_x86_64.s

 // -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 // 
-// ***** BEGIN LICENSE BLOCK *****
-// Version: MPL 1.1/GPL 2.0/LGPL 2.1
-//
-// The contents of this file are subject to the Mozilla Public License Version
-// 1.1 (the "License"); you may not use this file except in compliance with
-// the License. You may obtain a copy of the License at
-// http://www.mozilla.org/MPL/
-//
-// Software distributed under the License is distributed on an "AS IS" basis,
-// WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
-// for the specific language governing rights and limitations under the
-// License.
-//
-// The Original Code is the Netscape Portable Runtime (NSPR).
-//
-// The Initial Developer of the Original Code is
-// Netscape Communications Corporation.
-// Portions created by the Initial Developer are Copyright (C) 2004
-// the Initial Developer. All Rights Reserved.
-//
-// Contributor(s):
-//
-// Alternatively, the contents of this file may be used under the terms of
-// either the GNU General Public License Version 2 or later (the "GPL"), or
-// the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
-// in which case the provisions of the GPL or the LGPL are applicable instead
-// of those above. If you wish to allow use of your version of this file only
-// under the terms of either the GPL or the LGPL, and not to allow others to
-// use your version of this file under the terms of the MPL, indicate your
-// decision by deleting the provisions above and replace them with the notice
-// and other provisions required by the GPL or the LGPL. If you do not delete
-// the provisions above, a recipient may use your version of this file under
-// the terms of any one of the MPL, the GPL or the LGPL.
-//
-// ***** END LICENSE BLOCK *****
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 // PRInt32 _PR_x86_64_AtomicIncrement(PRInt32 *val)
 //
 // Atomically increment the integer pointed to by 'val' and return
 // the result of the increment.
 //
     .text
     .globl _PR_x86_64_AtomicIncrement
     .type _PR_x86_64_AtomicIncrement, @function
     .align 4
@@ skipping 49 matching lines @@
 _PR_x86_64_AtomicAdd:
     movl %esi, %eax
     lock
     xaddl %eax, (%rdi)
     addl %esi, %eax
     ret
     .size _PR_x86_64_AtomicAdd, .-_PR_x86_64_AtomicAdd
 
 // Magic indicating no need for an executable stack
 .section .note.GNU-stack, "", @progbits ; .previous