platform: msm8996: program the datapath mode for hdmi

Program the datapath mode for hdmi to enable support for legacy
operation, hdmi scrambler, and HDCP 2.2 functionality.

Change-Id: Ibb3e89a8bcfe242b61230f228129f6d0da4c351d
diff --git a/platform/msm_shared/mdss_hdmi.c b/platform/msm_shared/mdss_hdmi.c
index 4908c19..103e1fc 100644
--- a/platform/msm_shared/mdss_hdmi.c
+++ b/platform/msm_shared/mdss_hdmi.c
@@ -656,13 +656,14 @@
 static void mdss_hdmi_set_mode(bool on)
 {
 	uint32_t val = 0;
-
 	if (on) {
 		/* tx on */
-		val = 0x1;
+		val |= BIT(0);
+		/* hdcp legacy mode*/
+		val |= BIT(31);
 
 		if (!mdss_hdmi_is_dvi_mode())
-			val |= 0x2;
+			val |= BIT(1);
 	}
 
 	writel(val, HDMI_CTRL);