arm: dts: ls1028a: enable internal RGMII delays for the LS1028A-QDS AR8035 PHY

There are no PCB trace delays on this board, so the PHY needs to enable
its internal ones in order to have a proper electrical connection to the
enetc MAC.

Fixes: b32e9a75 ("arm: dts: ls1028a updates for network interfaces")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>