test/zdtm/cwd00: remove redundant chdir()

Label 'out' and chdir() below it are just redundant. Remove them
to make test simple.

Signed-off-by: Yicheng Qin <yichengq@google.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>