Revert "net: axienet: convert to phylink API"

commit  463696d729d05ad26a4059c89cfe55e85024421b from
https://github.com/Xilinx/linux-xlnx.git

 xlnx_rebase_v5.4

This reverts commit f5203a3d.
There are reported link issues with SGMII and 1000Base-x MLO_AN_PHY
mode. To fix it we are in discussion with mainline and Russell
suggested extension to phylink framework and modification to axieth
driver which is work in progress. For now revert phylink support
till all xilinx usecases are supported and functional in the
mainline tree.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lkml.org/lkml/2020/1/27/603


State: not-upstreamable
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>