Otherwise the Python network object continues to report that it is
attempting to connect.
Also make the return error code consistent with wifi scan.
Signed-off-by: Damien George <damien@micropython.org>
This makes sure deinit() can be called on the interface many times without
error, and that the state of the driver is fully reset.
Fixes issue #7493.
Signed-off-by: Damien George <damien@micropython.org>
