kcm: Destroy mutex in kcm_exit_net()

stable inclusion
from stable-v5.10.195
commit 46f02fc7f6fb1c10c483730df51230f99293aef4
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I95JOC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=46f02fc7f6fb1c10c483730df51230f99293aef4



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[ Upstream commit 6ad40b36 ]

kcm_exit_net() should call mutex_destroy() on knet->mutex. This is especially
needed if CONFIG_DEBUG_MUTEXES is enabled.

Fixes: ab7ac4eb ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Link: https://lore.kernel.org/r/20230902170708.1727999-1-syoshida@redhat.com


Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>