BaseTools:Fix issue caused by 84a52d4d03

The commit 84a52d4d03 will introduce
the new issue "Invalid offset value for Dynamic Vpd PCD". This patch
will fix the new issue, add 'DEFAULT' sku in to the AvailableSkuIdSet
variable.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: ZhiqiangX Zhao <zhiqiangx.zhao@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Cc: Bob Feng <bob.c.feng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

BaseTools/Source/Python/Workspace/DscBuildData.py

@@ -1415,6 +1415,7 @@ class DscBuildData(PlatformBuildClassObject):
         Pcds = AllPcds
         DefaultStoreMgr = DefaultStore(self.DefaultStores)
         SkuIds = self.SkuIds
+        self.SkuIdMgr.AvailableSkuIdSet.update({TAB_DEFAULT:0})
         DefaultStores = {storename for pcdobj in AllPcds.values() for skuobj in pcdobj.SkuInfoList.values() for storename in skuobj.DefaultStoreDict}
 
         S_PcdSet = []