Merge branch 'devlink-Use-nla_policy-to-validate-range'

Parav Pandit says:

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devlink: Use nla_policy to validate range

This two small patches uses nla_policy to validate user specified
fields are in valid range or not.

Patch summary:
Patch-1 checks the range of eswitch mode field
Patch-2 checks for the port type field. It eliminates a check in
code by using nla policy infrastructure.
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Reviewed-by: Jakub Kicinski <[email protected]>
Signed-off-by: David S. Miller <[email protected]>