treewide: make use of PTR_ERR_OR_ZERO ...

PTR_ERR_OR_ZERO is designed to replace boiler plate like:

	if (IS_ERR(x))
		return PTR_ERR(x);
	return 0;

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

drivers: net: convert drivers to spdx ...

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Reviewed-by: Roland Hieber <r.hieber@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

net: designware: make sure DMA is disabled on kernel start. ...

Halt is not automatically executed if we start the kernel.
So, we may have potentially memory corruptions.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

net: designware: add missing headers ...

As the eth_device and mii_bus structs are allocated inside the
dw_eth_dev struct a forward declaration isn't enough.

Fixes: c1f902841ce3 (net: designware: move probe to generic driver)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

net: designware: move probe to generic driver ...

The designware ethernet core is used on multiple different SoCs.
The linux kernel has a generic driver and SoC-specific drivers.
Do the same here.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>