Function try_lock

uspace/lib/cpp/include/__bits/thread/mutex.hpp:467–470

    template<class L1, class L2, class... L3>
    int try_lock(L1& l1, L2& l2, L3&... ls)
    {
        return aux::try_lock_tail(0, l1, l2, ls...);
    }

    namespace aux
    {