marlin/eas: Fixing foreground/schedtune.boost path

BUG: 28378389
Change-Id: Iea0bdf33de2ae2b9abc37460a9100d5044699c7d
diff --git a/services/surfaceflinger/surfaceflinger.rc b/services/surfaceflinger/surfaceflinger.rc
index 2b4ea2a..435aa0c 100644
--- a/services/surfaceflinger/surfaceflinger.rc
+++ b/services/surfaceflinger/surfaceflinger.rc
@@ -3,4 +3,4 @@
     user system
     group graphics drmrpc readproc
     onrestart restart zygote
-    writepid /sys/fs/cgroup/stune/foreground/tasks
+    writepid /dev/stune/foreground/tasks