Because of PHYLINK conversion we stopped parsing the phy-handle property
from DT. Unfortunatelly, some wrapper drivers still rely on this phy
node to configure the PHY.

Let's restore the parsing of PHY handle while these wrapper drivers are
not fully converted to PHYLINK.

Fixes: 74371272 ("net: stmmac: Convert to phylink and remove phylib logic")
Reported-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>