Some warnings when compiling the HomeKit server files

[AramVartanyan]

Hi Maxim,

I just want to mention that with the most recent changes there is one warning present:

/project/components/common/homekit/src/port.c:58:62: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
mdns_server_set_addr4(mdns_server, ((struct in_addr)(&ip.ip)));

It sounds little bit disturbing. Is it ignorable?

And the other one is:

/project/components/common/homekit/src/json.c:85:9: warning: unknown option after '#pragma GCC diagnostic' kind [-Wpragmas]
#pragma GCC diagnostic ignored "-Wimplicit-fallthrough"

Regards