fix iov_iter_bvec() "direction" argument

stable inclusion
from stable-v5.10.168
commit 0c67fb7775086a7159980153ad8518746e7a6b64
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7URR4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0c67fb7775086a7159980153ad8518746e7a6b64



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[ Upstream commit b676668d ]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: zhaoxiaoqiang11 <zhaoxiaoqiang11@jd.com>