net: fix phy_string_for_interface

net: fix phy_string_for_interface

commit ffb0f6f488b9 ("treewide: Rename PHY_INTERFACE_MODE_NONE to
PHY_INTERFACE_MODE_NA") broke the phy_string_for_interface function.
Fix it.

Fixes ffb0f6f488b9 ("treewide: Rename PHY_INTERFACE_MODE_NONE to PHY_INTERFACE_MODE_NA")
Signed-off-by: Tim Harvey <[email protected]>
Cc: Marek Behún <[email protected]>
Cc: Stefan Roese <[email protected]>
Cc: Ramon Fried <[email protected]>
Cc: Vladimir Oltean <[email protected]>
Reviewed-by: Stefan Roese <[email protected]>
Reviewed-by: Marek Behún <[email protected]>
Reviewed-by: Ramon Fried <[email protected]>