Null-check device properties when removing the address mapping

Test: mmm packages/modules/Bluetooth
Test: Manual | CtsVerifier app > Bluetooth Test > Insecure Client and Insecure
Flag: com.android.bluetooth.flags.temporary_pairing_device_properties
Bug: 341196265
Bug: 342202557
Change-Id: I0547a4de40e328b9f549c280994cfeecc17e9cd4