Since OpenSSH 7.8, the ProxyJump directive accepts the value "none"[1]
to override and clear a setting that might otherwise be contributed by
another (wildcard) host entry.
[1] https://bugzilla.mindrot.org/show_bug.cgi?id=2869
Change-Id: Ia35e82c6f8c58d5c6b8040cda7a07b220f43fc21
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>