net: phy: c45: don't use temporary linkmode bitmaps in genphy_c45_ethtool_get_eee

genphy_c45_eee_is_active() populates both bitmaps only if it returns
successfully. So we can avoid the overhead of the temporary bitmaps.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/b0832102-28ab-4223-b879-91fb1fc11278@gmail.com


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