crypto: return CHECK_OK in VerifyCallback

VerifyCallback returns 1 in two locations but CHECK_CERT_REVOKED in a
third return statment. This commit suggests that CHECK_OK is used
instead of 1. CHECK_OK is also used as the return value in
CheckWhitelistedServerCert so it seems to be consitent change to make.

PR-URL: #13241
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

src/node_crypto.cc

@@ -2867,14 +2867,14 @@ inline int VerifyCallback(int preverify_ok, X509_STORE_CTX* ctx) {
   // Failure on verification of the cert is handled in
   // Connection::VerifyError.
   if (preverify_ok == 0 || X509_STORE_CTX_get_error(ctx) != X509_V_OK)
-    return 1;
+    return CHECK_OK;
 
   // Server does not need to check the whitelist.
   SSL* ssl = static_cast<SSL*>(
       X509_STORE_CTX_get_ex_data(ctx, SSL_get_ex_data_X509_STORE_CTX_idx()));
 
   if (SSL_is_server(ssl))
-    return 1;
+    return CHECK_OK;
 
   // Client needs to check if the server cert is listed in the
   // whitelist when it is issued by the specific rootCAs.