openvswitch: Fix double reporting of drops in dropwatch

stable inclusion
from stable-v5.10.150
commit 4398e8a7fd6abf9cdfc69ee2a75434bf47c2a210
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0XA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4398e8a7fd6abf9cdfc69ee2a75434bf47c2a210



--------------------------------

[ Upstream commit 1100248a ]

Frames sent to userspace can be reported as dropped in
ovs_dp_process_packet, however, if they are dropped in the netlink code
then netlink_attachskb will report the same frame as dropped.

This patch checks for error codes which indicate that the frame has
already been freed.

Signed-off-by: Mike Pattrick <mkp@redhat.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2109946


Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>