Constify option parameter for better compiler analysis

runtime/parsec/codelets/codelet_ztile_zero.c

runtime/parsec/codelets/codelet_ztradd.c

runtime/parsec/codelets/codelet_ztrasm.c

runtime/parsec/codelets/codelet_ztrmm.c

runtime/parsec/codelets/codelet_ztrsm.c

runtime/parsec/codelets/codelet_ztrssq.c

runtime/parsec/codelets/codelet_ztrtri.c

runtime/parsec/codelets/codelet_ztslqt.c

runtime/parsec/codelets/codelet_ztsmlq.c

runtime/parsec/codelets/codelet_ztsmqr.c

runtime/parsec/codelets/codelet_ztsqrt.c

runtime/parsec/codelets/codelet_ztstrf.c

runtime/parsec/codelets/codelet_zttlqt.c

runtime/parsec/codelets/codelet_zttmlq.c

runtime/parsec/codelets/codelet_zttmqr.c

runtime/parsec/codelets/codelet_zttqrt.c

runtime/parsec/codelets/codelet_zunmlq.c

runtime/parsec/codelets/codelet_zunmqr.c

runtime/quark/codelets/codelet_dataflush.c

runtime/quark/codelets/codelet_zasum.c