OpenBSD removed the <sys/timeb.h> include from the OS with version 5.5.
Since them, compiling fails for clucene because of the predefined
availability of <sys/timeb.h> in qclucene-config_p.h. #ifdef the define
for timeb.h with !defined(__OpenBSD__) to avoid compile errors.

See hint in http://www.openbsd.org/faq/upgrade55.html



Change-Id: Ic4f787bed90a667d5e1c6fb28ea891585fcf08a4
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>