net: wifi: re-add `WIFI_MGMT_FORCED_PASSIVE_SCAN`

Re-add the `WIFI_MGMT_FORCED_PASSIVE_SCAN` option removed in #62751.
Now that `struct wifi_scan_params` is a reasonable size, we can enforce
the passive scan request even when no parameter struct is supplied by
the user.

Signed-off-by: Jordan Yates <jordan.yates@data61.csiro.au>