[7/X] Clean up logging in CDM

Make sure all log tags in com.android.server.companion prefixed with
"CompanionDevice" (allows for easy log filtering all CDM logs).

Make sure all Log.x() calls in com.android.server.companion are behind
DEBUG flags, while none of the Slog.x() calls are behind the DEBUG flag.

Bug: 211398735
Test: atest CtsCompanionDeviceManagerCoreTestCases
Test: atest CtsCompanionDeviceManagerUiAutomationTestCases
Test: atest CtsOsTestCases:CompanionDeviceManagerTest
Change-Id: Ied5cc355de463ab262d7ce73583283317c6d9d28