audio: Align api2aidl_NativeType_AudioDeviceDescription with native

Update 'AidlConversion.api2aidl_NativeType_AudioDeviceDescription'
to match its native counterpart. Enhance the test to prevent
future misalignment.

Bug: 402026998
Test: atest AidlConversionUnitTests
Change-Id: I9509b4b14339817c30b56f38e34378f9de910ebb