MediaFormat: deprecate KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT

Deprecate AAC-specific key KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT,
whose usage can be replaced by the codec agnostic key
KEY_MAX_OUTPUT_CHANNEL_COUNT.

Bug: 204239218
Test: atest DecoderTestAacFormat
Change-Id: Iad24e511eeee95266a4e9a7f70904968e27afc6d
2 files changed