AudioPort.h: Fix Compiler Warning

```
Conditional expression between different enumeration types ('audio_input_flags_t' and 'audio_output_flags_t') is deprecated
```
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:910fb0f5c759af31576bc18905064ad4d62d58bb)
Merged-In: I471d43e47968b61b9aaec4e5c159aff568d93aae
Change-Id: I471d43e47968b61b9aaec4e5c159aff568d93aae