Rename check_chain_extensions to check_chain

The function does much more than just checking extensions.
Reviewed-by: NDavid von Oheimb <david.von.oheimb@siemens.com>
Reviewed-by: NNicola Tuveri <nic.tuv@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/12683)

crypto/x509/v3_purp.c

@@ -431,7 +431,7 @@ int x509v3_cache_extensions(X509 *x)
             x->ex_flags |= EXFLAG_CA;
         if (bs->pathlen != NULL) {
             /*
-             * the error case !bs->ca is checked by check_chain_extensions()
+             * the error case !bs->ca is checked by check_chain()
              * in case ctx->param->flags & X509_V_FLAG_X509_STRICT
              */
             if (bs->pathlen->type == V_ASN1_NEG_INTEGER) {

crypto/x509/x509_vfy.c

@@ -69,7 +69,7 @@ static int dane_verify(X509_STORE_CTX *ctx);
 static int null_callback(int ok, X509_STORE_CTX *e);
 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
-static int check_chain_extensions(X509_STORE_CTX *ctx);
+static int check_chain(X509_STORE_CTX *ctx);
 static int check_name_constraints(X509_STORE_CTX *ctx);
 static int check_id(X509_STORE_CTX *ctx);
 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
@@ -222,7 +222,7 @@ static int verify_chain(X509_STORE_CTX *ctx)
      * instantiate chain public key parameters.
      */
     if ((ok = build_chain(ctx)) == 0 ||
-        (ok = check_chain_extensions(ctx)) == 0 ||
+        (ok = check_chain(ctx)) == 0 ||
         (ok = check_auth_level(ctx)) == 0 ||
         (ok = check_id(ctx)) == 0 || 1)
         X509_get_pubkey_parameters(NULL, ctx->chain);
@@ -441,7 +441,7 @@ static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
  * purpose
  */
 
-static int check_chain_extensions(X509_STORE_CTX *ctx)
+static int check_chain(X509_STORE_CTX *ctx)
 {
     int i, must_be_ca, plen = 0;
     X509 *x;