BaseTools/Plugin/CodeQL: Add CodeQL build plugin

Adds a CodeQL plugin that supports CodeQL in the build system.

1. CodeQlBuildPlugin - Generates a CodeQL database for a given build.
2. CodeQlAnalyzePlugin - Analyzes a CodeQL database and interprets
   results.
3. External dependencies - Assist with downloading the CodeQL CLI and
   making it available to the CodeQL plugins.
4. CodeQlQueries.qls - A C/C++ CodeQL query set run against the code.
5. Readme.md - A comprehensive readme file to help:
   - Platform integrators understand how to configure the plugin
   - Developers understand how to modify the plugin
   - Users understand how to use the plugin

Read Readme.md for additional details.

Cc: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Rebecca Cran <rebecca@bsdio.com>
Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Yuwei Chen <yuwei.chen@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Yuwei Chen <yuwei.chen@intel.com>
Reviewed-by: Sean Brogan <sean.brogan@microsoft.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Michael D Kinney <michael.d.kinney@intel.com>

BaseTools/Plugin/CodeQL/CodeQlBuild_plug_in.yaml

@@ -0,0 +1,13 @@
+## @file CodeQlBuild_plug_in.py
+#
+# Build plugin used to produce a CodeQL database from a build.
+#
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+##
+
+{
+  "scope": "codeql-build",
+  "name": "CodeQL Build Plugin",
+  "module": "CodeQlBuildPlugin"
+}