net: phy: simplify a check in phy_check_link_status

Handling case err == 0 in the other branch allows to simplify the
code. In addition I assume in "err & phydev->eee_cfg.tx_lpi_enabled"
it should have been a logical and operator. It works as expected also
with the bitwise and, but using a bitwise and with a bool value looks
ugly to me.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/de37bf30-61dd-49f9-b645-2d8ea11ddb5d@gmail.com


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