[openssl/openssl] 22eb38: Never use `__atomic_*` on macOS 10.7 and 10.8

[Tomas Mraz]

  Branch: refs/heads/openssl-3.0
  Home:   https://github.openssl.org/openssl/openssl
  Commit: 22eb3863845b898fcefdc2122586795bb5e9bcdf
      https://github.openssl.org/openssl/openssl/commit/22eb3863845b898fcefdc2122586795bb5e9bcdf
  Author: Kirill A. Korinsky <kirill at korins.ky>
  Date:   2022-04-22 (Fri, 22 Apr 2022)

  Changed paths:
    M crypto/threads_pthread.c

  Log Message:
  -----------
  Never use `__atomic_*` on macOS 10.7 and 10.8

macOS 10.7 and 10.8 had a bit wired clang which is detected as
`__GNUC__` which has `__ATOMIC_ACQ_REL` but it excepts one option at
`__atomic_is_lock_free` instead of 2.

This prevents OpenSSL to be compiled on such systems.

Fixes: #18055

Signed-off-by: Kirill A. Korinsky <kirill at korins.ky>

Reviewed-by: Paul Dale <pauli at openssl.org>
Reviewed-by: Tomas Mraz <tomas at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/18056)

(cherry picked from commit d39de4792dbdb6ab5f78c79d52d0210b44584538)