net: stmmac: Fallback to VLAN Perfect filtering if HASH is not available

net: stmmac: Fallback to VLAN Perfect filtering if HASH is not available

If VLAN Hash Filtering is not available we can fallback to perfect
filtering instead. Let's implement this in XGMAC and GMAC cores and let
the user use this filter.

VLAN VID=0 always passes filter so we check if more than 2 VLANs are
created and return proper error code if so because perfect filtering
only supports 1 VID at a time.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>