wifi: implement certificate HAL callback for Trust On First Use support

Bug: 196180536
Test: atest VtsHalWifiSupplicantStaIfaceTargetTest \
            VtsHalWifiSupplicantStaNetworkTargetTest \
            VtsHalWifiSupplicantP2pIfaceTargetTest

Change-Id: Ifdba307dee9003054f897db57a9f207ebc198cb4
6 files changed