BaseTools: Fix the bug to correctly check Pcd type that in FDF file

We set Pcd value in FDF and used this Pcd as PatchableInModule type in
module, it cause build report generate failure. because we incorrectly
set the Pcd type during check whether the Pcd is used.

Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Yonghong Zhu <yonghong.zhu@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>