p2p: support find a specific channel

Bug: 159094739
Test: atest VtsHalWifiSupplicantStaIfaceTargetTest \
            VtsHalWifiSupplicantStaNetworkTargetTest \
            VtsHalWifiSupplicantP2pIfaceTargetTest
Change-Id: Ia55b0b13588f9df39a53ccc945c43f2ba7c962f1
3 files changed