net/mlx5: reduce log level in hash list registration

net/mlx5: reduce log level in hash list registration

In mlx5 internal hash list tool, there is a log print when an entry
allocation is failed: Can't allocate hash list entry.

Some initialization checks triggers hash list registration in order to
check some capabilities. Here, the failure in registration doesn't
lead to failure in the initialization flow, that is why the log level
can be lower.

Move the entry allocation failure log to debug level.

Signed-off-by: Matan Azrad <matan@nvidia.com>
Reviewed-by: Asaf Penso <asafp@nvidia.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>