b53_get_mac_eee() sets both eee_enabled and eee_active, and then
returns zero.

dsa_slave_get_eee(), which calls this function, will then continue to
call phylink_ethtool_get_eee(), which will return -EOPNOTSUPP if there
is no PHY present, otherwise calling phy_ethtool_get_eee() which in
turn will call genphy_c45_ethtool_get_eee().

genphy_c45_ethtool_get_eee() will overwrite eee_enabled and eee_active
with its own interpretation from the PHYs settings and negotiation
result.

Thus, when there is no PHY, dsa_slave_get_eee() will fail with
-EOPNOTSUPP, meaning eee_enabled and eee_active will not be returned to
userspace. When there is a PHY, eee_enabled and eee_active will be
overwritten by phylib, making the setting of these members in
b53_get_mac_eee() entirely unnecessary.

Remove this code, thus simplifying b53_get_mac_eee().
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/E1rWbNI-002cCz-4x@rmk-PC.armlinux.org.ukSigned-off-by: Jakub Kicinski <kuba@kernel.org>