octeontx2-af: Update correct mask to filter IPv4 fragments

During the initial design, the IPv4 ip_flag mask was set to 0xff.
Which results to filter only fragmets with (fragment_offset == 0).
As part of the fix, updated the mask to 0x20 to filter all the
fragmented packets irrespective of the fragment_offset value.

Fixes: c672e372 ("octeontx2-pf: Add support to filter packet based on IP fragment")
Signed-off-by: Suman Ghosh <sumang@marvell.com>
Signed-off-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Sai Krishna <saikrishnag@marvell.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c

@@ -544,7 +544,7 @@ static int otx2_tc_prepare_flow(struct otx2_nic *nic, struct otx2_tc_flow *node,
 		if (match.mask->flags & FLOW_DIS_IS_FRAGMENT) {
 			if (ntohs(flow_spec->etype) == ETH_P_IP) {
 				flow_spec->ip_flag = IPV4_FLAG_MORE;
-				flow_mask->ip_flag = 0xff;
+				flow_mask->ip_flag = IPV4_FLAG_MORE;
 				req->features |= BIT_ULL(NPC_IPFRAG_IPV4);
 			} else if (ntohs(flow_spec->etype) == ETH_P_IPV6) {
 				flow_spec->next_header = IPPROTO_FRAGMENT;