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.

The inheritance flags are now correctly applied when restoring the security
descriptor, preserving the original permission structure.

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