cifs: Fix xid leak in cifs_flock()

stable inclusion
from stable-v5.10.152
commit 2d08311aa3056a84bfdc09bc47777de6a9b16c30
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I73HJ0

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2d08311aa3056a84bfdc09bc47777de6a9b16c30



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[ Upstream commit 575e079c ]

If not flock, before return -ENOLCK, should free the xid,
otherwise, the xid will be leaked.

Fixes: d0677992 ("cifs: add support for flock")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Lipeng Sang <sanglipeng1@jd.com>