Fix error in accessing IP config

mynit/boot.py

@@ -199,7 +199,7 @@ class _MynitBoot:
             else:
                 print("Invalid wifi mode %s" % self._config["wifi"]["mode"])
 
-            if self._config["wifi"]["ip"]["address"]:
+            if self._config["wifi"]["address"]:
                 ip_config = (
                     self._config["wifi"]["address"],
                     self._config["wifi"]["netmask"],