[Patch] Build Spec: Add some clarification of Build report section

[Yonghong Zhu <yonghong.zhu@intel.com>]

1. Add the section header of Global PCD Section
2. Add 'INF DEFAULT' in the module PCD section

Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Kevin W Shaw <kevin.w.shaw@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yonghong Zhu <yonghong.zhu@intel.com>
---
 13_build_reports/136_global_pcd_section.md | 13 +++++++++++++
 13_build_reports/138_module_section.md     |  8 +++++---
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/13_build_reports/136_global_pcd_section.md b/13_build_reports/136_global_pcd_section.md
index 2b7cf5f..0e3afa7 100644
--- a/13_build_reports/136_global_pcd_section.md
+++ b/13_build_reports/136_global_pcd_section.md
@@ -45,10 +45,23 @@ gEfiNt32PkgTokenSpaceGuid
 ```
 
 PCD values derived from expressions or other PCDs are not differentiated in the
 report. Only the final value is displayed.
 
+The section header is:
+```
+>===============================================================================<
+Platform Configuration Database Report
+  *B  - PCD override in the build option
+  *P  - Platform scoped PCD override in DSC file
+  *F  - Platform scoped PCD override in FDF file
+  *M  - Module scoped PCD override
+=================================================================================
+.. (List of PCDs)
+<===============================================================================>
+```
+
 Each global PCD item contains one or more lines:
 
 ### 13.6.1 Required line
 
 The first line is required:
diff --git a/13_build_reports/138_module_section.md b/13_build_reports/138_module_section.md
index 52288d7..843ad34 100644
--- a/13_build_reports/138_module_section.md
+++ b/13_build_reports/138_module_section.md
@@ -241,15 +241,17 @@ Each PCD may contain up to following lines:
      ```
      *F PcdVpdSample : DYN-VPD (UINT32) = 0x1 (1)
                        0x0001FFF
      ```
 
-3. The third and fourth lines are both option if the module's final
-   `<PcdValue>` is not equal to the PCD value in the PCD common section in the
-   DSC file and the PCD value in the DEC file respectively.
+3. The `DSC DEFAULT` `INF DEFAULT` and `DEC DEFAULT` are option if the module's
+   final `<PcdValue>` is not equal to the PCD value in the PCD common section in
+   DSC file, the PCD value in the module INF file and the PCD value in the DEC
+   file respectively.
    ```
    DSC DEFAULT = <Value in PCD Common Section in DSC>
+   INF DEFAULT = <Value in module INF>
    DEC DEFAULT = <Value in DEC>
    ```
    For example:
    ```
    *M PcdDebugPrintErrorLevel : FIXED   (UINT32) = 0x80000042 (2147483714)
-- 
2.6.1.windows.1