wifi: cfg80211: debugfs: fix return type in ht40allow_map_read()

stable inclusion
from stable-v5.10.142
commit 6855efbaf54a9bff0871f0acedc6c63186ae6c58
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6CSFH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6855efbaf54a9bff0871f0acedc6c63186ae6c58



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[ Upstream commit d776763f ]

The return type is supposed to be ssize_t, which is signed long,
but "r" was declared as unsigned int.  This means that on 64 bit systems
we return positive values instead of negative error codes.

Fixes: 80a3511d ("cfg80211: add debugfs HT40 allow map")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YutvOQeJm0UjLhwU@kili


Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: Zheng Zengkai <zhengzengkai@huawei.com>