Set system UID for internal discover peer message

Internal messages doesn't have a package name. So
set sending UID to system UID in internal discover
peer message to pass the permission checks and process
the message.

Bug: 264623515
Test: atest com.android.server.wifi.p2p.WifiP2pServiceImplTest
Change-Id: Icb34b89429876c28586dd9758d14f49c813ce7d6
Merged-In: Icb34b89429876c28586dd9758d14f49c813ce7d6
2 files changed