The RTL8366S/RB support connecting a second mac to it and using the 5th
port as an independent phy. Therefore we need to handle autonegotiation
changes for phy 4 like on a single phy device.
This fixes#7980, verified on a WNDR3700.
Signed-off-by: Jonas Gorski <jonas.gorski+openwrt@gmail.com>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@23127 3c298f89-4303-0410-b956-a3cf2f4a3e73