s3: torture: Add additional POSIX mkdir tests.

s3: torture: Add additional POSIX mkdir tests.

Ensure that if POSIX_foo exists as a file
we return the correct error code NT_STATUS_OBJECT_PATH_NOT_FOUND
if we try and traverse it as a directory.

Also ensure creation/deletion of POSIX_foo/foo fails
for directories and files with NT_STATUS_OBJECT_PATH_NOT_FOUND
if the directory POSIX_foo/ doesn't exist.

knownfail is back :-).

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13803

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>
(cherry picked from commit 632d0db8c42d50f5eecd002d9573f739cd945960)