net: dsa: microchip: Fix reserved multicast address table programming

net: dsa: microchip: Fix reserved multicast address table programming

KSZ9477/KSZ9897 and LAN937X families of switches use a reserved multicast
address table for some specific forwarding with some multicast addresses,
like the one used in STP.  The hardware assumes the host port is the last
port in KSZ9897 family and port 5 in LAN937X family.  Most of the time
this assumption is correct but not in other cases like KSZ9477.
Originally the function just setups the first entry, but the others still
need update, especially for one common multicast address that is used by
PTP operation.

LAN937x also uses different register bits when accessing the reserved
table.

Fixes: 457c182af597 ("net: dsa: microchip: generic access to ksz9477 static and reserved table")
Signed-off-by: Tristram Ha <tristram.ha@microchip.com>
Tested-by: Łukasz Majewski <lukma@nabladev.com>
Link: https://patch.msgid.link/20251105033741.6455-1-Tristram.Ha@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>