drm/radeon/dpm: implement force performance levels for 7xx/eg/btc

Allows you to limit the selected power levels via sysfs.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/btc_dpm.c b/drivers/gpu/drm/radeon/btc_dpm.c
index f072660..9156744 100644
--- a/drivers/gpu/drm/radeon/btc_dpm.c
+++ b/drivers/gpu/drm/radeon/btc_dpm.c
@@ -2326,9 +2326,9 @@
 		return ret;
 	}
 
-	ret = rv770_unrestrict_performance_levels_after_switch(rdev);
+	ret = rv770_dpm_force_performance_level(rdev, RADEON_DPM_FORCED_LEVEL_AUTO);
 	if (ret) {
-		DRM_ERROR("rv770_unrestrict_performance_levels_after_switch failed\n");
+		DRM_ERROR("rv770_dpm_force_performance_level failed\n");
 		return ret;
 	}