sysctl: Make the directories have nlink == 1

I goofed when I made sysctl directories have nlink == 0.
nlink == 0 means the directory has been deleted.
nlink == 1 meands a directory does not count subdirectories.

Use the default nlink == 1 for sysctl directories.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

fs/proc/proc_sysctl.c

@@ -253,7 +253,6 @@ static struct inode *proc_sys_make_inode(struct super_block *sb,
 		inode->i_fop = &proc_sys_file_operations;
 	} else {
 		inode->i_mode |= S_IFDIR;
-		clear_nlink(inode);
 		inode->i_op = &proc_sys_dir_operations;
 		inode->i_fop = &proc_sys_dir_file_operations;
 	}