EIGEN_MAX_ALIGN_BYTES can be zero when vectorization is disabled. In that...

EIGEN_MAX_ALIGN_BYTES can be zero when vectorization is disabled. In that case, checking for alignment boundaries breaks due to division by zero. But in these cases the check itself is redundant, so replace EIGEN_MAX_ALIGN_BYTES with std::max(1, EIGEN_MAX_ALIGN_BYTES).

PiperOrigin-RevId: 209513729