drm: sun4i: hdmi: Fix inverted HPD result

When the extra HPD polling in sun4i_hdmi was removed, the result of
HPD was accidentally inverted.

Fix this by inverting the check.

Fixes: bda8eaa6 ("drm: sun4i: hdmi: Remove extra HPD polling")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Tested-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200711011030.21997-1-wens@kernel.org

drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c

@@ -260,7 +260,7 @@ sun4i_hdmi_connector_detect(struct drm_connector *connector, bool force)
 	unsigned long reg;
 
 	reg = readl(hdmi->base + SUN4I_HDMI_HPD_REG);
-	if (reg & SUN4I_HDMI_HPD_HIGH) {
+	if (!(reg & SUN4I_HDMI_HPD_HIGH)) {
 		cec_phys_addr_invalidate(hdmi->cec_adap);
 		return connector_status_disconnected;
 	}