nfp: devlink: use the generic manufacture identifier instead of vendor

Vendor may sound ambiguous, let's rename the fab string to
"board.manufacture" (which was just added as a generic identifier).

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>