BaseTools: include variable namespace GUIDs of HII PCDs in Guid.xref

[PcdsDynamicHii]
gFooTokenSpaceGuid.PcdBar|L"Variable"|gVarNameSpaceGuid|0x0|FALSE|NV,BS

This patch add the variable namespace GUIDs in "Guid.xref" that are
used with dynamic HII PCDs.

Fixes: https://bugzilla.tianocore.org/show_bug.cgi?id=452
Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Zhiju.Fan <zhijux.fan@intel.com>
Reviewed-by: Yonghong Zhu <yonghong.zhu@intel.com>
diff --git a/BaseTools/Source/Python/GenFds/GenFds.py b/BaseTools/Source/Python/GenFds/GenFds.py
index 2307a19..9dec9c5 100644
--- a/BaseTools/Source/Python/GenFds/GenFds.py
+++ b/BaseTools/Source/Python/GenFds/GenFds.py
@@ -603,12 +603,23 @@
     def GenerateGuidXRefFile(BuildDb, ArchList, FdfParserObj):

         GuidXRefFileName = os.path.join(GenFdsGlobalVariable.FvDir, "Guid.xref")

         GuidXRefFile = BytesIO('')

+        PkgGuidDict = {}

         GuidDict = {}

         ModuleList = []

         FileGuidList = []

         GuidPattern = gGuidPattern

         for Arch in ArchList:

             PlatformDataBase = BuildDb.BuildObject[GenFdsGlobalVariable.ActivePlatform, Arch, GenFdsGlobalVariable.TargetName, GenFdsGlobalVariable.ToolChainTag]

+            PkgList = GenFdsGlobalVariable.WorkSpace.GetPackageList(GenFdsGlobalVariable.ActivePlatform, Arch, GenFdsGlobalVariable.TargetName, GenFdsGlobalVariable.ToolChainTag)

+            for P in PkgList:

+                PkgGuidDict.update(P.Guids)

+            for Name, Guid in PlatformDataBase.Pcds:

+                Pcd = PlatformDataBase.Pcds[Name, Guid]

+                if Pcd.Type in [TAB_PCDS_DYNAMIC_HII, TAB_PCDS_DYNAMIC_EX_HII]:

+                    for SkuId in Pcd.SkuInfoList:

+                        Sku = Pcd.SkuInfoList[SkuId]

+                        if Sku.VariableGuid and Sku.VariableGuid in PkgGuidDict.keys():

+                            GuidDict[Sku.VariableGuid] = PkgGuidDict[Sku.VariableGuid]

             for ModuleFile in PlatformDataBase.Modules:

                 Module = BuildDb.BuildObject[ModuleFile, Arch, GenFdsGlobalVariable.TargetName, GenFdsGlobalVariable.ToolChainTag]

                 if Module in ModuleList: