net: sched: fix erspan_opt settings in cls_flower

[ Upstream commit 29220780 ]

When matching erspan_opt in cls_flower, only the (version, dir, hwid)
fields are relevant. However, in fl_set_erspan_opt() it initializes
all bits of erspan_opt and its mask to 1. This inadvertently requires
packets to match not only the (version, dir, hwid) fields but also the
other fields that are unexpectedly set to 1.

This patch resolves the issue by ensuring that only the (version, dir,
hwid) fields are configured in fl_set_erspan_opt(), leaving the other
fields to 0 in erspan_opt.

Fixes: 79b1011c ("net: sched: allow flower to match erspan options")
Reported-by: Shuang Li <shuali@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>