net: stmmac: skip VLAN restore when VLAN hash ops are missing

net: stmmac: skip VLAN restore when VLAN hash ops are missing

stmmac_vlan_restore() unconditionally calls stmmac_vlan_update() when
NETIF_F_VLAN_FEATURES is set. On platforms where priv->hw->vlan (or
->update_vlan_hash) is not provided, stmmac_update_vlan_hash() returns
-EINVAL via stmmac_do_void_callback(), resulting in a spurious
"Failed to restore VLANs" error even when no VLAN filtering is in use.

Remove not needed comment.
Remove not used return value from stmmac_vlan_restore().

Tested on Orange Pi Zero 3.

Fixes: bd7ad51253a7 ("net: stmmac: Fix VLAN HW state restore")
Signed-off-by: Michal Piekos <michal.piekos@mmpsystems.pl>
Link: https://patch.msgid.link/20260328-vlan-restore-error-v4-1-f88624c530dc@mmpsystems.pl
Signed-off-by: Jakub Kicinski <kuba@kernel.org>