Remove unused file

Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5267)

crypto/bn/asm/x86.pl

-#! /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
-
-push(@INC,"perlasm","../../perlasm");
-require "x86asm.pl";
-
-require("x86/mul_add.pl");
-require("x86/mul.pl");
-require("x86/sqr.pl");
-require("x86/div.pl");
-require("x86/add.pl");
-require("x86/sub.pl");
-require("x86/comba.pl");
-
-$output = pop;
-open STDOUT,">$output";
-
-&asm_init($ARGV[0]);
-
-&bn_mul_add_words("bn_mul_add_words");
-&bn_mul_words("bn_mul_words");
-&bn_sqr_words("bn_sqr_words");
-&bn_div_words("bn_div_words");
-&bn_add_words("bn_add_words");
-&bn_sub_words("bn_sub_words");
-&bn_mul_comba("bn_mul_comba8",8);
-&bn_mul_comba("bn_mul_comba4",4);
-&bn_sqr_comba("bn_sqr_comba8",8);
-&bn_sqr_comba("bn_sqr_comba4",4);
-
-&asm_finish();
-
-close STDOUT;