Bugfix: Correctly restore ACL inheritance state on Windows

Since security descriptor backups were added in restic 0.17.0, Access Control Entry
inheritance was not restored correctly on Windows: restored permissions were always marked
as explicit (not inherited) even when they were inherited from a parent folder.

Now the inheritance flags are correctly applied when restoring the security
descriptor, so the original permission structure is preserved.

https://github.com/restic/restic/issues/5427
https://github.com/restic/restic/pull/5465
