orinoco: always use latest BSS info when caching scan results

Always copy the latest BSS information from the firmware's results to
the driver's BSS table to ensure that everything is up-to-date (IEs,
supported rates, encryption status, etc).

Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>