drm/radeon: clean up audio supported check

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/r600_audio.c

@@ -57,10 +57,7 @@ static bool radeon_dig_encoder(struct drm_encoder *encoder)
  */
 static int r600_audio_chipset_supported(struct radeon_device *rdev)
 {
-	return (rdev->family >= CHIP_R600 && !ASIC_IS_DCE6(rdev))
-		|| rdev->family == CHIP_RS600
-		|| rdev->family == CHIP_RS690
-		|| rdev->family == CHIP_RS740;
+	return ASIC_IS_DCE2(rdev) && !ASIC_IS_DCE6(rdev);
 }
 
 struct r600_audio r600_audio_status(struct radeon_device *rdev)