vec_set_vector_length
extern int vec_set_vector_length(struct task_struct *task, enum vec_type type,
ret = vec_set_vector_length(current, ARM64_VEC_SVE, vl, flags);
ret = vec_set_vector_length(current, ARM64_VEC_SME, vl, flags);
ret = vec_set_vector_length(target, ARM64_VEC_SME, header.vl,
ret = vec_set_vector_length(target, type, header.vl,