p2p: check p2p instance in all asynchronized callbacks

If cancelConnect is not called, the scan retry callback
would be called several times. If P2P is disabled in this period,
these asynchronized callbacks would access de-initialized p2p
instance and result in native crash.

Bug: 141773120
Test: atest VtsHalWifiSupplicantP2pV1_2TargetTest
Change-Id: Ifc1b397a6c48044b3ef10f110cd89186e2e27a8d
1 file changed