drm/radeon/dpm: fixup dynamic state adjust for sumo

Use a dedicated copy of the current power state since
we may have to adjust it on the fly.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index db31f20..0c33887 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -1289,6 +1289,7 @@
 	struct radeon_ps        *boot_ps;
 	/* default uvd power state */
 	struct radeon_ps        *uvd_ps;
+	struct radeon_ps        hw_ps;
 	enum radeon_pm_state_type state;
 	enum radeon_pm_state_type user_state;
 	u32                     platform_caps;