misc: mei: client.c: fix problem of return '-EOVERFLOW' in mei_cl_write

stable inclusion
from stable-v6.6.7
commit f78fff4648bb0a797359dac69792463efd22bb00
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8SSQ4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f78fff4648bb0a797359dac69792463efd22bb00



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[ Upstream commit ee6236027218f8531916f1c5caa5dc330379f287 ]

Clang static analyzer complains that value stored to 'rets' is never
read.Let 'buf_len = -EOVERFLOW' to make sure we can return '-EOVERFLOW'.

Fixes: 8c8d964c ("mei: move hbuf_depth from the mei device to the hw modules")
Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20231120095523.178385-2-suhui@nfschina.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>