dpaa_eth: support all modes with rate adapting PHYs

Stop removing modes that are not supported on the system interface
when the connected PHY is capable of rate adaptation. This addresses
an issue with the LS1046ARDB board 10G interface no longer working
with an 1G link partner after autonegotiation support was added
for the Aquantia PHY on board in

commit 09c4c57f ("net: phy: aquantia: add support for auto-negotiation configuration")

Before this commit the values advertised by the PHY were not
influenced by the dpaa_eth driver removal of system-side unsupported
modes as the aqr_config_aneg() was basically a no-op. After this
commit, the modes removed by the dpaa_eth driver were no longer
advertised thus autonegotiation with 1G link partners failed.

Reported-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Signed-off-by: Madalin Bucur <madalin.bucur@oss.nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>