[openssl/openssl] 9ff970: Check whether the pubkey exists in ossl_ecx_key_dup

[lanM]

  Branch: refs/heads/openssl-3.1
  Home:   https://github.com/openssl/openssl
  Commit: 9ff970674b296f6b53f41e77d81beac7e8526cac
      https://github.com/openssl/openssl/commit/9ff970674b296f6b53f41e77d81beac7e8526cac
  Author: lan1120 <lanming at huawei.com>
  Date:   2024-01-16 (Tue, 16 Jan 2024)

  Changed paths:
    M crypto/ec/ecx_backend.c
    M test/evp_pkey_provided_test.c

  Log Message:
  -----------
  Check whether the pubkey exists in ossl_ecx_key_dup

Signed-off-by: lan1120 <lanming at huawei.com>

Reviewed-by: Shane Lontis <shane.lontis at oracle.com>
Reviewed-by: Tomas Mraz <tomas at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/22984)

(cherry picked from commit aac531e5daa2edec5d47e702a7f115cf77fe07f9)