Interworking: Try to use same BSS entry for storing GAS results

Interworking: Try to use same BSS entry for storing GAS results

There may be cases where multiple BSS entries for a single BSSID are in
the table. This is mostly in automated test cases due to the AP
configuration changes, but something similar could potentially happen as
a corner case in more realistic networks, too, e.g., when an AP changes
its operating channel. Make network selection more robust by trying to
find the exact BSS entry instead of any BSS entry with a matching BSSID
when storing GAS/ANQP response.

Signed-hostap: Jouni Malinen <j@w1.fi>