IB/core: Add CapabilityMask2 to port attributes

CapabilityMask2 was added in IB Spec 1.3 under PortInfo attribute.  The
new Capapbility mask is needed in order to expose the new 2X width and HDR
speed.

Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>