[PATCH] common/mlx5: fix MR lookup on slow path

[Thomas Monjalon]

> > Memory region (MR) was being looked up incorrectly for the data address of
> > an externally-attached mbuf.
> > A search was attempted for the mempool of the mbuf, while mbuf data
> > address does not belong to this mempool in case of externally-attached mbuf.
> > Only attempt the search:
> > 1) for not externally-attached mbufs;
> > 2) for mbufs coming from MPRQ mempool;
> > 3) for externally-attached mbufs from mempools
> >    with pinned external buffers.
> > 
> > Fixes: 08ac03580ef2 ("common/mlx5: fix mempool registration")
> > 
> > Signed-off-by: Dmitry Kozlyuk <dkozlyuk at nvidia.com>
> > Reviewed-by: Matan Azrad <matan at nvidia.com>
> Acked-by: Viacheslav Ovsiienko <viacheslavo at nvidia.com>

Applied as last-minute critical fix.