leaudio: Fix build on Linux

This fixes the build issues on Linux introduced by
(926fd43c: leaudio: Add BAP and CSIP integration...)

Bug: 150670922
Bug: 203206209
Tag: #floss
Test: ./build.py on Linux and mma -j "system/bt" on Android
Change-Id: I5b146d301d919780791d354720ae74a88c5b60ef