net: phy: realtek: fix handling of RTL8105e-integrated PHY

[ No applicable upstream commit ]

After the referenced fix it turned out that one particular RTL8168
chip version (RTL8105e) does not work on 5.4 because no dedicated PHY
driver exists. Adding this PHY driver was done for fixing a different
issue for versions from 5.5 already. I re-send the same change for 5.4
because the commit message differs.

Fixes: 2e8c339b ("r8169: fix PHY driver check on platforms w/o module softdeps")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>