tools: Fix bytes<->str mixing in python3
diff --git a/tools/hardirqs.py b/tools/hardirqs.py
index 4e373d9..239d813 100755
--- a/tools/hardirqs.py
+++ b/tools/hardirqs.py
@@ -241,7 +241,7 @@
         print("%-8s\n" % strftime("%H:%M:%S"), end="")
 
     if args.dist:
-        dist.print_log2_hist(label, "hardirq")
+        dist.print_log2_hist(label, "hardirq", section_print_fn=bytes.decode)
     else:
         print("%-26s %11s" % ("HARDIRQ", "TOTAL_" + label))
         for k, v in sorted(dist.items(), key=lambda dist: dist[1].value):