BaseTools: Dsc/Fdf conditional statement parse issue

Set PCD value with --pcd argument not replace DSC/Fdf PCD value.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yunhua Feng <yunhuax.feng@intel.com>
Reviewed-by: Yonghong Zhu <yonghong.zhu@intel.com>

BaseTools/Source/Python/GenFds/FdfParser.py

@@ -925,6 +925,10 @@ class FdfParser:
 
         MacroDict.update(GlobalData.gGlobalDefines)
         MacroDict.update(GlobalData.gCommandLineDefines)
+        if GlobalData.BuildOptionPcd:
+            for Item in GlobalData.BuildOptionPcd:
+                PcdName, TmpValue = Item.split("=")
+                MacroDict[PcdName.strip()] = TmpValue
         # Highest priority
 
         return MacroDict