Function check_nosignal

src/bthread/butex.cpp:288–290

nosignal is true & tag is same can return true

//  nosignal is true & tag is same can return true
inline bool check_nosignal(bool nosignal, bthread_tag_t tag) {
    return nosignal && is_same_tag(tag);
}

// if tag is same return tls_task_group else choose one group with tag
inline TaskGroup* get_task_group(TaskControl* c, bthread_tag_t tag) {