BCM5325 doesn't implement UC_FLOOD_MASK, MC_FLOOD_MASK and IPMC_FLOOD_MASK
registers.
This has to be handled differently with other pages and registers.
Fixes: a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags")
Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>