octeon_ep: Add driver framework and device initialization

Add driver framework and device setup and initialization for Octeon
PCI Endpoint NIC.

Add implementation to load module, initilaize, register network device,
cleanup and unload module.

Signed-off-by: Veerasenareddy Burru <vburru@marvell.com>
Signed-off-by: Abhijit Ayarekar <aayarekar@marvell.com>
Signed-off-by: Satananda Burla <sburla@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>