net: dsa: xrs700x: forward HSR supervision frames

Forward supervision frames between redunant HSR ports. This was broken
in the last commit.

Fixes: 1a42624a ("net: dsa: xrs700x: allow HSR/PRP supervision dupes for node_table")
Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>