Merge branch 'Renesas-rz-n1'

Merge branch 'Renesas-rz-n1'

Clément Léger says:

====================
net: add support for Renesas RZ/N1 ethernet su

The Renesas RZ/N1 SoCs features an ethernet subsystem which contains
(most notably) a switch, two GMACs, and a MII converter [1]. This
series adds support for the switch and the MII converter.

The MII converter present on this SoC has been represented as a PCS
which sit between the MACs and the PHY. This PCS driver is probed from
the device-tree since it requires to be configured. Indeed the MII
converter also contains the registers that are handling the muxing of
ports (Switch, MAC, HSR, RTOS, etc) internally to the SoC.

The switch driver is based on DSA and exposes 4 ports + 1 CPU
management port. It include basic bridging support as well as FDB and
statistics support.

Link: [1] https://www.renesas.com/us/en/document/mah/rzn1d-group-rzn1s-group-rzn1l-group-users-manual-r-engine-and-ethernet-peripherals

-----
Changes in V9:
- Cover letter:
  - Remove comment about RZN1 patches that are now in the master branch.
- Commits:
  - Add Vladimir Oltean Reviewed-by
- PCS:
  - Add "Depends on OF" for PCS_RZN1_MIIC due to error found by intel
    kernel test robot <lkp@intel.com>.
  - Check return value of of_property_read_u32() for
    "renesas,miic-switch-portin" property before setting conf.
  - Return miic_parse_dt() return value in miic_probe() on error
- Switch:
  - Add "Depends on OF" for NET_DSA_RZN1_A5PSW due to errors found by
    intel kernel test robot <lkp@intel.com>.
- DT:
  - Add spaces between switch port and '{'
====================

Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>