qcom_mdio: add initial IPQ4018 MDIO support

[adrian]

Summary

This adds support for the IPQ4018/IPQ4019 MDIO bus. This is used to
talk to external PHYs and switches. (There's an internal switch
in the IPQ4018/IPQ4019 as well, but it's accessible via MMIO/AXI.)

[manu]

sys/dev/qcom_mdio/qcom_mdio_ipq4018.c

295

1/ Does it needs to be that early ? INTERRUPT is really early in the boot, we have BUS_PASS_SUPPORTDEV that usually work for driver like that.
2/ Do you really need to be on simplebus and ofwbus ? In the DTS it's under /soc which is simple-bus compatible so I don't think you need the ofwbus declaration.

[manu]

mdio and ofw* part looks good, only two questions for me.

[adrian]

Update dates

[adrian]

update dates

[adrian]

sys/dev/qcom_mdio/qcom_mdio_debug.h

35

....... whoops, i should fix that

[adrian]

Fix debug

[adrian]

address more things

[adrian]

update id