drm/radeon: remove null test before kfree

Fix checkpatch warning:
WARNING: kfree(NULL) is safe this check is probably not required

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_pm.c

@@ -1400,9 +1400,7 @@ static void radeon_pm_fini_old(struct radeon_device *rdev)
 	}
 
 	radeon_hwmon_fini(rdev);
-
-	if (rdev->pm.power_state)
-		kfree(rdev->pm.power_state);
+	kfree(rdev->pm.power_state);
 }
 
 static void radeon_pm_fini_dpm(struct radeon_device *rdev)
@@ -1421,9 +1419,7 @@ static void radeon_pm_fini_dpm(struct radeon_device *rdev)
 	radeon_dpm_fini(rdev);
 
 	radeon_hwmon_fini(rdev);
-
-	if (rdev->pm.power_state)
-		kfree(rdev->pm.power_state);
+	kfree(rdev->pm.power_state);
 }
 
 void radeon_pm_fini(struct radeon_device *rdev)