[openssl/openssl] 969327: Fix Configure test for -mips in CFLAGS

[Mike Gilbert]

  Branch: refs/heads/OpenSSL_1_1_1-stable
  Home:   https://github.com/openssl/openssl
  Commit: 969327390220aee7515a4054d5189186402d6687
      https://github.com/openssl/openssl/commit/969327390220aee7515a4054d5189186402d6687
  Author: Mike Gilbert <floppym at gentoo.org>
  Date:   2023-03-17 (Fri, 17 Mar 2023)

  Changed paths:
    M Configure

  Log Message:
  -----------
  Fix Configure test for -mips in CFLAGS

We want to add -mips2 or -mips3 only if the user hasn't already
specified a mips version in CFLAGS. The existing test was a
double-negative.

CLA: trivial

Fixes: https://github.com/openssl/openssl/issues/20214

Reviewed-by: Matt Caswell <matt at openssl.org>
Reviewed-by: Shane Lontis <shane.lontis at oracle.com>
Reviewed-by: Paul Dale <pauli at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/20536)