net: phylink: pass supported host PHY interface modes to phylib for SFP's PHYs

Pass the supported PHY interface types to phylib if the PHY we are
connecting is inside a SFP, so that the PHY driver can select an
appropriate host configuration mode for their interface according to
the host capabilities.

For example the Marvell 88X3310 PHY inside RollBall SFP modules
defaults to 10gbase-r mode on host's side, and the marvell10g
driver currently does not change this setting. But a host may not
support 10gbase-r. For example Turris Omnia only supports sgmii,
1000base-x and 2500base-x modes. The PHY can be configured to use
those modes, but in order for the PHY driver to do that, it needs
to know which modes are supported.

Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>