MdePkg/MdePkg.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.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

MdePkg/MdePkg.ci.yaml

@@ -2,6 +2,7 @@
 # CI configuration for MdePkg
 #
 # Copyright (c) Microsoft Corporation
+# Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 ##
 {
@@ -9,6 +10,17 @@
     "LicenseCheck": {
         "IgnoreFiles": []
     },
+    "EccCheck": {
+        ## Exception sample looks like below:
+        ## "ExceptionList": [
+        ##     "<ErrorID>", "<KeyWord>"
+        ## ]
+        "ExceptionList": [
+        ],
+        ## Both file path and directory path are accepted.
+        "IgnoreFiles": [
+        ]
+    },
     ## options defined ci/Plugin/CompilerPlugin
     "CompilerPlugin": {
         "DscPath": "MdePkg.dsc"