net: dsa: ocelot_ext: remove unnecessary phylink.h include

During review of ocelot_ext, it created a private phylink instance
that wasn't necessary. This was removed for subsequent postings,
but the include file seems to have been left behind. Remove it.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>