rmixl_vec_establish
ih = rmixl_vec_establish(RMIXL_INTRVEC_FMN, -1, RMIXL_FMN_INTR_IPL,
void *ih = rmixl_vec_establish(vec, 0, IPL_SCHED, NULL, NULL, false);
void * const ih = rmixl_vec_establish(vec, -1, IPL_SCHED,
ih = rmixl_vec_establish(vec, cpumask, ipl, func, arg, mpsafe);
extern void *rmixl_vec_establish(int, int, int,