doc: fix socket.readyState state descriptions

[samuel871211]

lib/net.js

ObjectDefineProperty(Socket.prototype, 'readyState', {
  __proto__: null,
  get: function() {
    if (this.connecting) {
      return 'opening';
    } else if (this.readable && this.writable) {
      return 'open';
    } else if (this.readable && !this.writable) {
      return 'readOnly';
    } else if (!this.readable && this.writable) {
      return 'writeOnly';
    }
    return 'closed';
  },
});

[nodejs-github-bot]

Review requested:

• @nodejs/net