MAINTAINERS: Add Arnaldo as tools/perf/ co-maintainer

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/MAINTAINERS b/MAINTAINERS
index 2533fc4..40ed22e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4221,6 +4221,7 @@
 M:	Peter Zijlstra <a.p.zijlstra@chello.nl>
 M:	Paul Mackerras <paulus@samba.org>
 M:	Ingo Molnar <mingo@elte.hu>
+M:	Arnaldo Carvalho de Melo <acme@redhat.com>
 S:	Supported
 F:	kernel/perf_event.c
 F:	include/linux/perf_event.h