MdeModulePkg/MdeModulePkg.ci.yaml: Add configuration for Ecc check

Add configuration ExceptionList and IgnoreFiles for package config
files. So users can rely on this to ignore some Ecc issues.
Besides, add submodule path in IgnoreFiles section.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

MdeModulePkg/MdeModulePkg.ci.yaml

@@ -2,6 +2,7 @@
 # CI configuration for MdeModulePkg
 #
 # Copyright (c) Microsoft Corporation
+# Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 ##
 {
@@ -9,6 +10,19 @@
     "LicenseCheck": {
         "IgnoreFiles": []
     },
+    "EccCheck": {
+        ## Exception sample looks like below:
+        ## "ExceptionList": [
+        ##     "<ErrorID>", "<KeyWord>"
+        ## ]
+        "ExceptionList": [
+        ],
+        ## Both file path and directory path are accepted.
+        "IgnoreFiles": [
+            "Library/BrotliCustomDecompressLib/brotli",
+            "Universal/RegularExpressionDxe/oniguruma"
+        ]
+    },
     ## options defined ci/Plugin/CompilerPlugin
     "CompilerPlugin": {
         "DscPath": "MdeModulePkg.dsc"