Align a few license headers with OpenSSL's "copyright consolidation"

This was another part of OpenSSL's "copyright consolidation" changes.
See:

https://github.com/openssl/openssl/blob/44c8a5e2b9af8909844cc002c53049311634b314/crypto/bn/asm/x86_64-gcc.c
https://github.com/openssl/openssl/blob/44c8a5e2b9af8909844cc002c53049311634b314/crypto/md5/asm/md5-586.pl
https://github.com/openssl/openssl/blob/44c8a5e2b9af8909844cc002c53049311634b314/crypto/md5/asm/md5-x86_64.pl

Bug: 364634028
Change-Id: I9bb24c94a468ca419936118f4d1e5b3a359e1674
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/74887
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/fipsmodule/bn/asm/x86_64-gcc.cc.inc b/crypto/fipsmodule/bn/asm/x86_64-gcc.cc.inc
index 4f6bcae..efdff48 100644
--- a/crypto/fipsmodule/bn/asm/x86_64-gcc.cc.inc
+++ b/crypto/fipsmodule/bn/asm/x86_64-gcc.cc.inc
@@ -1,3 +1,12 @@
+/*
+ * Copyright 2002-2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
 /* x86_64 BIGNUM accelerator version 0.1, December 2002.
  *
  * Implemented by Andy Polyakov <appro@fy.chalmers.se> for the OpenSSL
diff --git a/crypto/md5/asm/md5-586.pl b/crypto/md5/asm/md5-586.pl
index f849b46..d020f67 100644
--- a/crypto/md5/asm/md5-586.pl
+++ b/crypto/md5/asm/md5-586.pl
@@ -1,4 +1,11 @@
-#!/usr/local/bin/perl
+#! /usr/bin/env perl
+# Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the OpenSSL license (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
 
 # Normal is the
 # md5_block_x86(MD5_CTX *c, ULONG *X);
diff --git a/crypto/md5/asm/md5-x86_64.pl b/crypto/md5/asm/md5-x86_64.pl
index eee50a3..80e2d3f 100644
--- a/crypto/md5/asm/md5-x86_64.pl
+++ b/crypto/md5/asm/md5-x86_64.pl
@@ -1,11 +1,13 @@
-#!/usr/bin/perl -w
-#
-# MD5 optimized for AMD64.
-#
+#! /usr/bin/env perl
 # Author: Marc Bevand <bevand_m (at) epita.fr>
-# Licence: I hereby disclaim the copyright on this code and place it
-# in the public domain.
+# Copyright 2005-2016 The OpenSSL Project Authors. All Rights Reserved.
 #
+# Licensed under the OpenSSL license (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+# MD5 optimized for AMD64.
 
 use strict;