autotest: Convert network_WiFiMatFunc/012CheckMaskedBSSID

Rewrite network_WiFiMatFunc/012CheckMaskedBSSID to use the new WiFi
framework.  In the process, move the logic to trigger a scan over to
WiFiClient.  Also expand hostapd_configure in site_linux_router to
handle SSID and BSSID configuration settings.

TEST=The following:
./run_remote_tests.sh --remote=chromeos1-shelf1-host4 wifi_masked_bssid
(Fails with TestNA because this is a RSPro cell)
./run_remote_tests.sh --remote=chromeos1-shelf1-host3 wifi_masked_bssid
(Passes)
./run_remote_tests.sh --remote=chromeos1-shelf1-host3 \
    network_WiFiRoaming --args='test_pat=006*'
(Passes; Verifies that scanning is working for older site_wifitest tests)
BUG=chromium:230660

Change-Id: I95ffbeb2cc0361fb98289fc8623fe6dfe33eb25d
Reviewed-on: https://gerrit.chromium.org/gerrit/50557
Commit-Queue: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Tested-by: Christopher Wiley <wiley@chromium.org>
9 files changed