net: hns3: Add STRP_TAGP field support for hardware revision 0x21

Hardware Revision(0x21) Buffer Descriptor adds a field STRP_TAGP
for vlan stripped processed indication. STRP_TAGP field has 2 bits,
bit 0 is stripped indication of the vlan tag in outer vlan tag
field, bit 1 is stripped indication of the vlan tag in inner vlan
tag field. For each bit, 0 indicates the tag is not stripped and
1 indicates the tag is stripped.

This patch adds STRP_TAGP support for revision(0x21), and does not
change the revision(0x20) action.

Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>