Use VLA instead of malloc for scratch

runtime/openmp/codelets/codelet_zgelqt.c

runtime/openmp/codelets/codelet_zgeqrt.c

runtime/openmp/codelets/codelet_zgetrf.c

runtime/openmp/codelets/codelet_zherfb.c

runtime/openmp/codelets/codelet_zlange.c

runtime/openmp/codelets/codelet_zlanhe.c

runtime/openmp/codelets/codelet_zlansy.c

runtime/openmp/codelets/codelet_zlantr.c

runtime/openmp/codelets/codelet_ztplqt.c

runtime/openmp/codelets/codelet_ztpmlqt.c

runtime/openmp/codelets/codelet_ztpmqrt.c

runtime/openmp/codelets/codelet_ztpqrt.c

runtime/openmp/codelets/codelet_ztslqt.c

runtime/openmp/codelets/codelet_ztsmlq.c

runtime/openmp/codelets/codelet_ztsmlq_hetra1.c

runtime/openmp/codelets/codelet_ztsmqr.c

runtime/openmp/codelets/codelet_ztsmqr_hetra1.c

runtime/openmp/codelets/codelet_ztsqrt.c

runtime/openmp/codelets/codelet_ztstrf.c

runtime/openmp/codelets/codelet_zttlqt.c