trivial: fix where cgroup documentation is not correctly referred to

cgroup documentation was moved to Documentation/cgroups/. There are some
places that still refer to Documentation/controllers/,
Documentation/cgroups.txt and Documentation/cpusets.txt. Fix those.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/Documentation/vm/numa_memory_policy.txt b/Documentation/vm/numa_memory_policy.txt
index 6aaaeb3..be45dbb 100644
--- a/Documentation/vm/numa_memory_policy.txt
+++ b/Documentation/vm/numa_memory_policy.txt
@@ -8,7 +8,8 @@
 document attempts to describe the concepts and APIs of the 2.6 memory policy
 support.
 
-Memory policies should not be confused with cpusets (Documentation/cpusets.txt)
+Memory policies should not be confused with cpusets
+(Documentation/cgroups/cpusets.txt)
 which is an administrative mechanism for restricting the nodes from which
 memory may be allocated by a set of processes. Memory policies are a
 programming interface that a NUMA-aware application can take advantage of.  When