init.raviole.rc: remove world writable on speaker.cal

Bug: 197039088
Test: do re-calibration and check the speaker.cal is updated.
adb shell crus_sp_cal -d -s -a --device 5 --ambient 27 --num-speaker 2 --verbosity 7

Change-Id: I7d8c43c5feaab4d0337590f268f0b59aa7f3e6fd
diff --git a/conf/init.raviole.rc b/conf/init.raviole.rc
index 45cc750..330eacf 100644
--- a/conf/init.raviole.rc
+++ b/conf/init.raviole.rc
@@ -40,7 +40,7 @@
     exec_background - system shell -- /vendor/bin/trusty_apploader /vendor/firmware/g6.app
 
     # Speaker amp permission
-    chmod 666 /mnt/vendor/persist/audio/speaker.cal
+    chmod 644 /mnt/vendor/persist/audio/speaker.cal
 
     # Start the twoshay touch service
     start twoshay