getrlimit.2: SEE ALSO: add cgroups(7)

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
diff --git a/man2/getrlimit.2 b/man2/getrlimit.2
index e407ad0..46c633c 100644
--- a/man2/getrlimit.2
+++ b/man2/getrlimit.2
@@ -799,4 +799,5 @@
 .BR ulimit (3),
 .BR core (5),
 .BR capabilities (7),
+.BR cgroups (7),
 .BR signal (7)