We had 4 identical copies of the check_repo_path function. Replace them by a
single copy in the build_tree module where it naturally belongs.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Copy of scripts/mbedtls_dev/build_tree.py from mbedtls-3.2.1,
backported to facilitate future backports of python scripts.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
