[Encode] Set Log2WeightDenomLuma to 0 in MFX AVC SLICE STATE

AVC VDEnc implicit mode weighted prediction requires Log2WeightDenomLuma = 0 in MFX AVC SLICE STATE.

Change-Id: I949a305d49e233ea27ea54663e2eba63ea3efedf

Author: Jabin_Wu

media_driver/agnostic/common/hw/vdbox/mhw_vdbox_mfx_generic.h

@@ -763,9 +763,17 @@ class MhwVdboxMfxInterfaceGeneric : public MhwVdboxMfxInterface
             cmd.DW3.WeightedPredictionIndicator = picParams->weighted_bipred_idc;
             if (picParams->weighted_bipred_idc == IMPLICIT_WEIGHTED_INTER_PRED_MODE)
             {
-                // SNB requirement
-                cmd.DW2.Log2WeightDenomLuma = 5;
-                cmd.DW2.Log2WeightDenomChroma = 5;
+                if (avcSliceState->bVdencInUse)
+                {
+                    cmd.DW2.Log2WeightDenomLuma = 0;
+                    cmd.DW2.Log2WeightDenomChroma = 0;
+                }
+                else
+                {
+                    // SNB requirement
+                    cmd.DW2.Log2WeightDenomLuma = 5;
+                    cmd.DW2.Log2WeightDenomChroma = 5;
+                }
             }
 
             cmd.DW9.Roundinterenable = avcSliceState->bRoundingInterEnable;