Merge branch 'dsa-sja1110'

Vladimir Oltean says:

====================
Add NXP SJA1110 support to the sja1105 DSA driver

The NXP SJA1110 is an automotive Ethernet switch with an embedded Arm
Cortex-M7 microcontroller. The switch has 11 ports (10 external + one
for the DSA-style connection to the microcontroller).
The microcontroller can be disabled and the switch can be controlled
over SPI, a la SJA1105 - this is how this driver handles things.

There are some integrated NXP PHYs (100base-T1 and 100base-TX). Their
initialization is handled by their own PHY drivers, the switch is only
concerned with enabling register accesses to them, by registering two
MDIO buses.

Changes in v3:
- Make sure the VLAN retagging port is enabled and functional
- Dropped SGMII PCS from this series

Changes in v2:
- converted nxp,sja1105 DT bindings to YAML
- registered the PCS MDIO bus and forced auto-probing off for all PHY
  addresses for this bus
- changed the container node name for the 2 MDIO buses from "mdio" to
  "mdios" to avoid matching on the mdio.yaml schema (it's just a
  container node, not an MDIO bus)
- fixed an uninitialized "offset" variable usage in
  sja1110_pcs_mdio_{read,write}
- using the mdiobus_c45_addr macro instead of open-coding that operation
====================

Signed-off-by: David S. Miller <davem@davemloft.net>