docs: cgroup-v1: add it to the admin-guide book

Those files belong to the admin guide, so add them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
diff --git a/init/Kconfig b/init/Kconfig
index 9eb92ee..381cdfe 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -821,7 +821,7 @@
 	  controls or device isolation.
 	  See
 		- Documentation/scheduler/sched-design-CFS.rst	(CFS)
-		- Documentation/cgroup-v1/ (features for grouping, isolation
+		- Documentation/admin-guide/cgroup-v1/ (features for grouping, isolation
 					  and resource control)
 
 	  Say N if unsure.
@@ -883,7 +883,7 @@
 	CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
 	CONFIG_BLK_DEV_THROTTLING=y.
 
-	See Documentation/cgroup-v1/blkio-controller.rst for more information.
+	See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information.
 
 config CGROUP_WRITEBACK
 	bool