Remove ln -t flag, not supported on Mac OS X
Remove ln -t flag, not supported on Mac OS X

Mac OS's command line is based on BSD, and the BSD variant of the ln
command does not have the -t option: [1].

* [1] http://www.freebsd.org/cgi/man.cgi?ln

Change-Id: Ib2ef8dff9429055f227c34dae5c19c20a019cd1f

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