msm: mdss: Support demo mode for post processing

Add demo mode feature for numerous post processing features. In dual pipe
case, demo mode allows for either the left or right pipe's feature to be
disabled to showcase its effects. Features supported include assertive
display, gamut mapping, panel gamma correction, inverse gamma correction,
dithering, picture adjustment (v2 only), and polynomial color correction.

Change-Id: I8bceeffc11967ff23497df7739e6f99c30d2b10f
Signed-off-by: Carl Vanderlip <carlv@codeaurora.org>
diff --git a/include/linux/msm_mdp.h b/include/linux/msm_mdp.h
index 724e573..4903939 100644
--- a/include/linux/msm_mdp.h
+++ b/include/linux/msm_mdp.h
@@ -802,6 +802,10 @@
 	DCM_BLANK,
 };
 
+#define MDSS_PP_SPLIT_LEFT_ONLY		0x10000000
+#define MDSS_PP_SPLIT_RIGHT_ONLY	0x20000000
+#define MDSS_PP_SPLIT_MASK		0x30000000
+
 #define MDSS_MAX_BL_BRIGHTNESS 255
 #define AD_BL_LIN_LEN 256