octeontx2-af: Add devlink suppoort to af driver

Add devlink support to AF driver. Basic devlink support is added.
Currently info_get is the only supported devlink ops.

devlink ouptput looks like this
 # devlink dev
 pci/0002:01:00.0
 # devlink dev info
 pci/0002:01:00.0:
  driver octeontx2-af
 #

Signed-off-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Jerin Jacob <jerinj@marvell.com>
Signed-off-by: George Cherian <george.cherian@marvell.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>