s V and T which determine
    Q as a block reflector I - V*T*V', and also the matrix Y = A * V.
    (Note this is different than LAPACK, which computes Y = A * V * T.)

    This is an auxiliary routine called by ZGEHRD.

    Arguments
    ---------
    @param[in]
    n       INTEGER
            The order of the matrix A.

    @param[in]
    k       INTEGER
            The offset for the reduction. Elements below the k-th
            subdiagonal in the first NB columns are reduced to zero.
            K < N.