HDMI: Do not start NewDeviceAction while DeviceDiscoveryAction is running

<Report Physical Address> processed by local device TV starts a
NewDeviceAction which can interfere with DeviceDiscoveryAction.

Flag: EXEMPT bugfix
Test: atest com.android.server.hdmi
Bug: 349007368
Change-Id: I1da6e45f852f3e8bab0b51003e7929a6904f80b9