net: hns3: fix query vlan mask value error for flow director

commit c75ec148 upstream.

Currently, the driver returns VLAN_VID_MASK for vlan mask field,
when get flow director rule information for rule doesn't use vlan.
It may cause the vlan mask value display as 0xf000 in this
case, like below:

estuary:/$ ethtool -u eth1
50 RX rings available
Total 1 rules

Filter: 2
Rule Type: TCP over IPv4
Src IP addr: 0.0.0.0 mask: 255.255.255.255
Dest IP addr: 0.0.0.0 mask: 255.255.255.255
TOS: 0x0 mask: 0xff
Src port: 0 mask: 0xffff
Dest port: 0 mask: 0xffff
VLAN EtherType: 0x0 mask: 0xffff
VLAN: 0x0 mask: 0xf000
User-defined: 0x1234 mask: 0x0
Action: Direct to queue 3

Fix it by return 0.

Fixes: 05c2314f

 ("net: hns3: Add support for rule query of flow director")
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>