filesystems: add set_nlink()

Replace remaining direct i_nlink updates with a new set_nlink()
updater function.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/hppfs/hppfs.c b/fs/hppfs/hppfs.c
index 970ea98..f590b11 100644
--- a/fs/hppfs/hppfs.c
+++ b/fs/hppfs/hppfs.c
@@ -702,7 +702,7 @@
 	inode->i_ctime = proc_ino->i_ctime;
 	inode->i_ino = proc_ino->i_ino;
 	inode->i_mode = proc_ino->i_mode;
-	inode->i_nlink = proc_ino->i_nlink;
+	set_nlink(inode, proc_ino->i_nlink);
 	inode->i_size = proc_ino->i_size;
 	inode->i_blocks = proc_ino->i_blocks;