net: phy: aquantia: Add support for rate matching

This adds support for rate matching for phys similar to the AQR107. We
assume that all phys using aqr107_read_status support rate matching.
However, it could be possible to determine support based on the firmware
revision if there are phys discovered which do not support rate
matching.  However, as rate matching is advertised in the datasheets for
these phys, I suspect it is supported most boards.

Despite the name, the "config" registers are updated with the current
rate matching method (if any). Because they appear to be updated
automatically, I don't know if these registers can be used to disable
rate matching.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>