net: mdio: hisi-femac: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: mdio: Move MDIO drivers into a new subdirectory

Move all the MDIO drivers and multiplexers into drivers/net/mdio. The
mdio core is however left in the phy directory, due to mutual
dependencies between the MDIO core and the PHY core.

Take this opportunity to sort the Kconfig based on the menuconfig
strings, and move the multiplexers to the end with a separating
comment.

v2:
Fix typo in commit message

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>