treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nfp: rename the driver and add new main file

Support for the PF driver is about to be added and will share
much of the code. When the VF driver was added we planned to
maintain the PF driver as a separate module but have decided
that for our simple use case just maintaining a single module
is more reasonable. Rename the driver to just "nfp" and update
the Kconfig.

While at it remove latent references to NFP3200.

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

net: add driver for Netronome NFP4000/NFP6000 NIC VFs

Add driver for Virtual Functions for the Netronome's
NFP-4000 and NFP-6000 based NICs.

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