staging: ks7010: Change 'device_open_status' to a bool.

The 'device_open_status' member of 'struct ks_wlan_private' is only
ever set to zero or one, so it makes more sense for it to be a bool
instead of an int.

Signed-off-by: Quytelda Kahja <quytelda@tamalin.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>