drm/i915: Use IS_HSW_ULT() in HSW CDCLK clock read-out

hsw_get_cdclk_freq() is really just HSW, so we can use IS_HSW_ULT()
instead of IS_ULT() there.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_ddi.c

@@ -1291,7 +1291,7 @@ static int hsw_get_cdclk_freq(struct drm_i915_private *dev_priv)
 		return 450000;
 	else if (freq == LCPLL_CLK_FREQ_450)
 		return 450000;
-	else if (IS_ULT(dev))
+	else if (IS_HSW_ULT(dev))
 		return 337500;
 	else
 		return 540000;