net: phylink: use pcs_neg_mode in phylink_mac_pcs_get_state()

As in-band AN no longer just depends on MLO_AN_INBAND + Autoneg bit,
we need to take account of the pcs_neg_mode when deciding how to
initialise the speed, duplex and pause state members before calling
into the .pcs_neg_mode() method. Add this.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/E1tXGeO-000Esx-0r@rmk-PC.armlinux.org.uk


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