nfsd: Clone should commit src file metadata too

mainline inclusion
from mainline-5.6-rc1
commit 57f64034
category: bugfix
bugzilla: 30516
CVE: NA

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vfs_clone_file_range() can modify the metadata on the source file too,
so we need to commit that to stable storage as well.

Reported-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Acked-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Reviewed-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>