Fix to handle non-blocking OCSP when WOLFSSL_NONBLOCK_OCSP is defined and not using async. OCSP callback should return OCSP_WANT_READ. Added ability to simulate non-blocking OCSP using TEST_NONBLOCK_CERTS.

examples/client/client.c

@@ -1582,8 +1582,13 @@ THREAD_RETURN WOLFSSL_THREAD client_test(void* args)
             wolfSSL_CTX_EnableOCSP(ctx, WOLFSSL_OCSP_NO_NONCE
                                                     | WOLFSSL_OCSP_URL_OVERRIDE);
         }
-        else
+        else {
             wolfSSL_CTX_EnableOCSP(ctx, 0);
+        }
+
+    #ifdef WOLFSSL_NONBLOCK_OCSP
+        wolfSSL_CTX_SetOCSP_Cb(ctx, OCSPIOCb, OCSPRespFreeCb, NULL);
+    #endif
     }
 #endif