C2 VTS: Disable multi-frame tests in audio decoder

AAC, AMRWB, AMRNB and MP3 decoders had multi-frame tests,
but this is not guaranteed to be supported by all decoders.

Also, similar tests were not added for flac, vorbis and opus as
those decoders do not support multi-frame input currently.
So multi-frame tests are removed for all codecs now.

Bug: 294262063
Bug: 299492907
Test: atest VtsHalMediaC2V1_0TargetAudioDecTest

Merged-In: I8084b48b4a181e87bd151bc2870eddad36ae3a0b
Change-Id: I8084b48b4a181e87bd151bc2870eddad36ae3a0b