Remove redundant prefixes from enums in audio common types and effects HAL

Since in generated C++ code class enums are used, the names of enum
values are scoped anyway, thus carrying the prefix only clutters
code.

For C enums, newly introduced "value_prefix" annotation is used
to add the required prefix.

Added annotations for effects HAL types are just informational,
but can be used would C headers generation ever be required.

Also:

  - renamed AudioInputFlags -> AudioInputFlag for consistency;

  - moved AUDIO_INTERLEAVE_... constants into their own enum.

Bug: 31800672
Change-Id: I5b325f3440e0057ca98c4617040c7e5a89d2283d
Test: make