Add a script to generate source manifests

The source manifest can be used by external tools to download source
files externally before initiating the bootstrap process.

The script prints the source manifest to stdout.

source-manifest.py

@@ -0,0 +1,34 @@
+#!/usr/bin/env python3
+"""
+A helper application used to get a list of source files required
+for the bootstrapping process.
+"""
+
+# SPDX-License-Identifier: GPL-3.0-or-later
+# SPDX-FileCopyrightText: 2023 Dor Askayo <dor.askayo@gmail.com>
+
+import argparse
+
+from sysa import SysA
+from sysc import SysC
+
+def main():
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument("-s", "--system",
+                        help="Generate source manifest for the specified systems",
+                        choices=["sysa", "sysc"],
+                        nargs="+",
+                        action="extend",
+                        required=True)
+
+    args = parser.parse_args()
+
+    if "sysa" in args.system:
+        print(SysA.get_source_manifest())
+
+    if "sysc" in args.system:
+        print(SysC.get_source_manifest())
+
+if __name__ == "__main__":
+    main()