Remove stray include of complex.h

already provided conditionally by common.h via openblas_utest.h
Unconditional inclusion breaks older Android and similar platforms that use OPENBLAS_COMPLEX_STRUCT

utest/test_dotu.c

@@ -32,7 +32,6 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 **********************************************************************************/
 
 #include "openblas_utest.h"
-#include <complex.h>
 
 CTEST( zdotu,zdotu_n_1)
 {