P2P: Fix hidl service discovery request

Check if the provided destination address is zero'd, and make it null.
Supplicant was treating the zero address as a real address, and not
broadcasting the service discovery request to devices.

Bug: 38174469
Test: CTS Verifier service discovery requester
Change-Id: Ifa9841e2c87f3e4e6f5201480fbf248cb0f97680
1 file changed