scripts/dl_github_archieve.py: fix generating unreproducible tar

Allign dl_github_archieve.py to 8252511dc0b5a71e9e64b96f233a27ad73e28b7f
change. On supported system the sigid bit is applied to files and tar
archieve that on tar creation. This cause unreproducible tar for these
system and these bit should be dropped to produce reproducible tar.

Add the missing option following the command options used in other
scripts.

Fixes: 75ab064d2b38 ("build: download code from github using archive API")
Suggested-by: Eneas U de Queiroz <[email protected]>
Tested-by: Robert Marko <[email protected]>
Signed-off-by: Christian Marangi <[email protected]>

scripts/dl_github_archive.py

@@ -133,7 +133,7 @@ class Path(object):
     def tar(path, subdir, into=None, ts=None):
         """Pack ``path`` into tarball ``into``."""
         # --sort=name requires a recent build of GNU tar
-        args = ['tar', '--numeric-owner', '--owner=0', '--group=0', '--sort=name']
+        args = ['tar', '--numeric-owner', '--owner=0', '--group=0', '--sort=name', '--mode=a-s']
         args += ['-C', path, '-cf', into, subdir]
         envs = os.environ.copy()
         if ts is not None: