Merge branch 'nfp-flower-handle-MTU-changes'

Jakub Kicinski says:

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nfp: flower: handle MTU changes

This set improves MTU handling for flower offload.  The max MTU is
correctly capped and physical port MTU is communicated to the FW
(and indirectly HW).
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Signed-off-by: David S. Miller <davem@davemloft.net>