Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c
index 31279a7..afb8d4f 100644
--- a/tools/perf/util/comm.c
+++ b/tools/perf/util/comm.c
@@ -1,11 +1,12 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "comm.h"
-#include "util.h"
 #include <errno.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <linux/refcount.h>
+#include <linux/rbtree.h>
+#include <linux/zalloc.h>
 #include "rwsem.h"
 
 struct comm_str {