Avoid network selection from scan during connection

Avoid network selection from scan during connection

If scan results arrive during the connection process, the network
selection function was called, interrupting the current connection.
While a regular scan is mutually exclusive with connection establishment
via the nature of radio work, there's no such protection for scheduled
scan. Prevent network selection while a connection is in progress.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>