drm/sun4i: Fix sun8i HDMI PHY configuration for > 148.5 MHz

Vendor provided documentation says that EMP bits should be set to 3 for
pixel clocks greater than 148.5 MHz.

Fix that.

Cc: stable@vger.kernel.org # 4.17+
Fixes: 4f86e817 ("drm/sun4i: Add support for H3 HDMI PHY variant")
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190514204337.11068-3-jernej.skrabec@siol.net

drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c

@@ -293,7 +293,8 @@ static int sun8i_hdmi_phy_config_h3(struct dw_hdmi *hdmi,
 				 SUN8I_HDMI_PHY_ANA_CFG2_REG_BIGSW |
 				 SUN8I_HDMI_PHY_ANA_CFG2_REG_SLV(4);
 		ana_cfg3_init |= SUN8I_HDMI_PHY_ANA_CFG3_REG_AMPCK(9) |
-				 SUN8I_HDMI_PHY_ANA_CFG3_REG_AMP(13);
+				 SUN8I_HDMI_PHY_ANA_CFG3_REG_AMP(13) |
+				 SUN8I_HDMI_PHY_ANA_CFG3_REG_EMP(3);
 	}
 
 	regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_ANA_CFG1_REG,