auth_identity: still use ASN1_STRING_data() for libssl < v1.1.0

- from libssl v1.1.0, ASN1_STRING_data() is deprecated, but before it
  doesn't exist
- reported by Victor Seva, GH #685

modules/auth_identity/auth_crypt.c

@@ -114,7 +114,11 @@ int check_x509_subj(X509 *pcert, str* sdom)
 
 			if (actname->type == GEN_DNS || actname->type == GEN_URI) {
 				/* we've found one */
+#if OPENSSL_VERSION_NUMBER >= 0x010100000L
 				altptr = (char *)ASN1_STRING_get0_data(actname->d.ia5);
+#else
+				altptr = (char *)ASN1_STRING_data(actname->d.ia5);
+#endif
 				if (actname->type == GEN_URI) {
 					if (parse_uri(altptr, strlen(altptr), &suri) != 0) {
 						continue;