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>

Makefile: drop -D__CHECK_ENDIAN__ from cflags

That's the default now, no need for makefiles to set it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>

alx: add a simple AR816x/AR817x device driver

This is a very simple driver, based on the original vendor
driver that Qualcomm/Atheros published/submitted previously,
but reworked to make the code saner. However, it also lost
a number of features (TSO/GSO, VLAN acceleration and multi-
queue support) in the process, as well as debugging support
features I didn't have any use for. The only thing I left
is checksum offload.

More features can obviously be added, but this seemed like
a good start for having a driver in mainline at all.

Johannes Stezenbach has verified that the driver works on
AR8161, I have a AR8171 myself. The E2200 device ID I found
on github in somebody's repository.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>