esp32 crash when no resolve

[alonmuroch]

How to reproduce:

• esp32-wroom-dev
• W5500 ethernet

When resolve times out a crash happens on MDNS.cpp:1429 due to ipAddr == NULL.
It's NULL because the function is called by MDNS.cpp:1429:1071

How to solve:
change MDNS:1071 to

if (i == 0) {
               byte* noneAddress = new byte[4]{0, 0, 0, };
               this->_finishedResolvingName((char*)this->_resolveNames[0], noneAddress);
            }

{255, 255, 255, 255} is equal to INADDR_NONE