common/mlx5: fix UAR allocation diagnostics messages

common/mlx5: fix UAR allocation diagnostics messages

Depending on kernel capabilities and rdma-core version the mapping of
UAR (User Access Region) of desired memory caching type (non-cached or
write combining) might fail. The PMD implements the flexible strategy
of UAR mapping, alternating the type of caching to succeed.

During this process the failure diagnostics messages are emitted.
These messages are merely diagnostics ones and the logging level should
be adjusted to DEBUG.

Fixes: 9cc0e99c81ab0 ("common/mlx5: share UAR allocation routine")
Cc: stable@dpdk.org
Signed-off-by: Michael Baum <michaelba@nvidia.com>
Reviewed-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>