fvp: Various fixups

1. Build default audio modules. Without these modules, logcat gets
   heavily flooded with:
        AudioSystem-JNI: AudioSystem::listAudioPorts error -19

2. Bring in hal_drm_clearkey.te from sepolicy/common for
   android.hardware.drm@1.2-service.clearkey. Symlink it instead of
   copying it to ease maintenance. This fixes:
        init    : Could not start service 'vendor.drm-clearkey-hal-1-2' as part of class 'hal'...

Test: boot fvp, check logcat
Change-Id: I4a75ed5510dce239436b3c375be22f1014dcda01
3 files changed