mdns component moved from idf 5.0

[kyrannian]

Before running idf.py menuconfig, run

idf.py add-dependency espressif/mdns^1.0.7

Reference : https://esp32.com/viewtopic.php?t=30959

[maximkulkin]

It's hard to keep track of it: in v5.0 they had removed mdns component, in latest master it is there back.

[kyrannian]

Painful for sure, just wanted to leave that there in case someone else runs into it.

[camow7]

This is really handy. Solves for the following error the first time you run the menuconfig config:

Failed to resolve component 'mdns'.