drm/amd/amdgpu: Don't proceed in audio_fini in DCEv11 if disabled
If amdgpu_audio is disabled then the audio structure is not initialized
so we shouldn't read it in the fini function.
Signed-off-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>