ionic: Add hardware init and device commands

The ionic device has a small set of PCI registers, including a
device control and data space, and a large set of message
commands.

Also adds new DEVLINK_INFO_VERSION_GENERIC tags for
ASIC_ID, ASIC_REV, and FW.

Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>