net: pcs: xpcs: move PCS reset to .pcs_pre_config()

Move the PCS reset to .pcs_pre_config() rather than at creation time,
which means we call the reset function with the interface that we're
actually going to be using to talk to the downstream device.

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> # sja1105
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Tested-by: for them?
Link: https://patch.msgid.link/E1svfMA-005ZI3-Va@rmk-PC.armlinux.org.uk


Signed-off-by: Jakub Kicinski <kuba@kernel.org>