Don't leave the open call as ambigious, causes a compile error on Ubuntu

Ubuntu has some secure functions that require open() calls to be explicit
rather than implied by the umask of the process. This is only when
O_CREATE is used.

Ref:https://github.com/facebook/hiphop-php/commit/f55604ba3d916ab39354af67852583ec79038710

Signed-off-by: Gokulnath Avanashilingam <Gokulnath.Avanashilingam@in.bosch.com>