Add remote/local IP/Port functions to WiFiClient

[esev]

I'd like to have this available before reintroducing meshtastic/firmware#5636

Tested with

    WiFiClient client(0);
    assert(client.connect("192.168.1.1", 22));
    printf("remote: %08x:%d\n", (uint32_t)client.remoteIP(), client.remotePort());
    printf("local: %08x:%d\n", (uint32_t)client.localIP(), client.localPort());

Result (the byte swapped IPs are expected):

remote: 0101a8c0:22
local: 020012ac:40334

Needed for meshtastic/firmware#5647

[CLAassistant]

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