Merge branch 'mlxsw-per-prio-tc-counters'

Jiri Pirko says:

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mlxsw: Add per-{Prio,TC} counters

Ido says:

Add per-priority and per-tc counters, which are very useful for debugging
purposes and fine-tuning.
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Signed-off-by: David S. Miller <davem@davemloft.net>