net: dsa: fix older DSA drivers using phylink

net: dsa: fix older DSA drivers using phylink

Older DSA drivers that do not provide an dsa_ops adjust_link method end
up using phylink. Unfortunately, a recent phylink change that requires
its supported_interfaces bitmap to be filled breaks these drivers
because the bitmap remains empty.

Rather than fixing each driver individually, fix it in the core code so
we have a sensible set of defaults.

Reported-by: Sergei Antonov <[email protected]>
Fixes: de5c9bf40c45 ("net: phylink: require supported_interfaces to be filled")
Signed-off-by: Russell King (Oracle) <[email protected]>
Reviewed-by: Vladimir Oltean <[email protected]>
Tested-by: Vladimir Oltean <[email protected]> # dsa_loop
Reviewed-by: Florian Fainelli <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>