crypto/provider_core.c: Allocate activatecnt_lock

crypto/provider_core.c: Allocate activatecnt_lock

CRYPTO_atomic_add has a lock as a parameter, which is often ignored, but in
some cases (for example, when BROKEN_CLANG_ATOMICS is defined) it is required.

There is no easy way to determine if the lock is needed or not. The current
logic looks like this:

    if defined(OPENSSL_THREADS) && !defined(CRYPTO_TDEBUG) && !defined(OPENSSL_SYS_WINDOWS)
      if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
        - It works without the lock, but in general the need for the
          lock depends on __atomic_is_lock_free results
      elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
        - The lock is not needed (unless ret is NULL, which should never
          happen?)
      else
        - The lock is required
      endif
    else
      - The lock is not needed
    endif

Adding such conditions outside of crypto.h is error-prone, so it is better to
always allocate the lock, otherwise CRYPTO_atomic_add may silently fail.

Fixes #23376.

CLA: trivial
Fixes: fc570b2605 ("Avoid taking a write lock in ossl_provider_doall_activated()")
Signed-off-by: Oleg Bulatov <oleg@bulatov.me>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/24081)