fix up cgroup warning

I just noticed this in mainline:

kernel/cgroup.c: In function `proc_cgroupstats_show':
kernel/cgroup.c:2405: warning: unused variable `root'

---

 linux-2.6.git-dave/kernel/cgroup.c |    1 -
 1 file changed, 1 deletion(-)

diff -puN kernel/cgroup.c~cgroup-warning kernel/cgroup.c

kernel/cgroup.c 2007-10-22 15:10:20.000000000 -0700 renamed from kernel/cgroup.c~cgroup-warning 2007-10-22 15:10:20.000000000 -0700 +0 -1

@@ -2402,7 +2402,6 @@ struct file_operations proc_cgroup_opera
 static int proc_cgroupstats_show(struct seq_file *m, void *v)
 {
        int i;
-       struct cgroupfs_root *root;
 
        seq_puts(m, "#subsys_name\thierarchy\tnum_cgroups\n");
        mutex_lock(&cgroup_mutex);

diff -L +2405 -puN /dev/null /dev/null
_