mlx4_core: Don't read reserved fields in mlx4_QUERY_ADAPTER()

The firmware QUERY_ADAPTER command does not return vendor_id,
device_id, and revision_id; eliminate these fields from the query.

Initialize the rev_id field of the mlx4 device via init_node_data (MAD
IFC query), as is done in the query_device verb implementation.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>