Merge changes I46d85902,Idba0ad35,Ic3718468,Ia1e40e1d,I501f8a02, ...

* changes:
  wpa_supplicant(hidl): Add ANQP stub methods
  wpa_supplicant(hidl): Add P2P stub methods
  wpa_supplicant(hidl): Invalidate objects in HidlManager
  wpa_supplicant(hidl): Use hidl_return_util in |P2pNetwork|
  wpa_supplicant(hidl): Use hidl_return_util in |P2pIface|
  wpa_supplicant(hidl): Use hidl_return_util in |StaNetwork|
  wpa_supplicant(hidl): Use hidl_return_util in |StaIface|
  wpa_supplicant(hidl): Use hidl_return_util in |Supplicant|
  wpa_supplicant(hidl): Helper functions for invoking hidl cont callbacks