Multi-Packet Rx queue uses PMD-managed buffers to store packets.
These buffers are externally attached to user mbufs.
This conflicts with the feature that allows using user-managed
externally attached buffers in an application.
Add the corresponding limitation to MLX5 documentation that MPRQ
and external data buffers cannot be used together.
Signed-off-by: Alexander Kozyrev <akozyrev@nvidia.com>
b60d006cd1