drm: i915: correct return status in intel_hdmi_mode_valid()

Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index f289b86..655bbd9 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -194,7 +194,7 @@
 	if (mode->clock > 165000)
 		return MODE_CLOCK_HIGH;
 	if (mode->clock < 20000)
-		return MODE_CLOCK_HIGH;
+		return MODE_CLOCK_LOW;
 
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 		return MODE_NO_DBLESCAN;