FIPS: Fix memory leak in digest_sign self-test

Contrary to what the documentation for EVP_DigestSignInit(3) and
EVP_DigestVerifyInit(3) says, the EVP_PKEY_CTX created by these
functions is not automatically released inside of the FIPS provider due
to an #ifndef FIPS_MODULE in evp_md_ctx_reset_ex.

Resolves: rhbz#2102535

0074-FIPS-Use-digest_sign-digest_verify-in-self-test.patch

@@ -247,7 +247,7 @@ index b6d5e8e134..77eec075e6 100644
      size_t siglen = sizeof(sig);
      static const unsigned char dgst[] = {
          0x7f, 0x83, 0xb1, 0x65, 0x7f, 0xf1, 0xfc, 0x53, 0xb9, 0x2d, 0xc1, 0x81,
-@@ -488,23 +491,22 @@ static int self_test_sign(const ST_KAT_SIGN *t,
+@@ -488,23 +491,26 @@ static int self_test_sign(const ST_KAT_SIGN *t,
          || EVP_PKEY_fromdata(kctx, &pkey, EVP_PKEY_KEYPAIR, params) <= 0)
          goto err;
  
@@ -279,12 +279,16 @@ index b6d5e8e134..77eec075e6 100644
  
 -    if (EVP_PKEY_sign(sctx, sig, &siglen, dgst, sizeof(dgst)) <= 0
 -        || EVP_PKEY_verify_init(sctx) <= 0
++    /* sctx is not freed automatically inside the FIPS module */
++    EVP_PKEY_CTX_free(sctx);
++    sctx = NULL;
++
 +    EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_FINALISE | EVP_MD_CTX_FLAG_ONESHOT);
 +    if (EVP_DigestVerifyInit(ctx, &sctx, md, NULL, pkey) <= 0
          || EVP_PKEY_CTX_set_params(sctx, params_sig) <= 0)
          goto err;
  
-@@ -518,14 +520,15 @@ static int self_test_sign(const ST_KAT_SIGN *t,
+@@ -509,14 +510,17 @@ static int self_test_sign(const ST_KAT_SIGN *t,
          goto err;
  
      OSSL_SELF_TEST_oncorrupt_byte(st, sig);
@@ -295,10 +299,12 @@ index b6d5e8e134..77eec075e6 100644
  err:
      BN_CTX_free(bnctx);
      EVP_PKEY_free(pkey);
+-    EVP_PKEY_CTX_free(kctx);
 +    EVP_MD_free(md);
 +    EVP_MD_CTX_free(ctx);
-     EVP_PKEY_CTX_free(kctx);
--    EVP_PKEY_CTX_free(sctx);
++    /* sctx is not freed automatically inside the FIPS module */
+     EVP_PKEY_CTX_free(sctx);
++    EVP_PKEY_CTX_free(kctx);
      OSSL_PARAM_free(params);
      OSSL_PARAM_free(params_sig);
      OSSL_PARAM_BLD_free(bld);