disp: msm: sde: add support for DS2 and DS3

Expand the DS enum and increase the DS max number
to support DS2 and DS3.

Change-Id: Iff8d591fece20528e30449c228db5cb2047cdded
Signed-off-by: Lei Chen <[email protected]>

include/uapi/display/drm/sde_drm.h

@@ -382,7 +382,7 @@ struct sde_drm_scaler_v2 {
 };
 
 /* Number of dest scalers supported */
-#define SDE_MAX_DS_COUNT 2
+#define SDE_MAX_DS_COUNT 4
 
 /*
  * Destination scaler flag config

msm/sde/sde_hw_mdss.h

@@ -229,6 +229,8 @@ enum sde_ds {
 	DS_TOP,
 	DS_0,
 	DS_1,
+	DS_2,
+	DS_3,
 	DS_MAX
 };