nfp: add support for reading nffw info

NFFW info is a resource which contains information about
the loaded application firmware.  Add code which will allow
us to decode it and retrieve MIP location.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>