raven: run trusty_apploader from system shell for faceauth

Bug: 182953825
Test: on device
Change-Id: I27ec828b4c8e80e2b1dcfdc480bca069e18ebf22
diff --git a/conf/init.raven.rc b/conf/init.raven.rc
index 9eb01b9..e7ba699 100644
--- a/conf/init.raven.rc
+++ b/conf/init.raven.rc
@@ -29,7 +29,7 @@
     exec_background - system shell -- /vendor/bin/trusty_apploader /vendor/firmware/g6.app
 
     # Face
-    exec_background /vendor/bin/trusty_apploader /vendor/firmware/faceauth.app
+    exec_background - system shell -- /vendor/bin/trusty_apploader /vendor/firmware/faceauth.app
 
 on property:mfgapi.touchpanel.permission=1
     chmod 0600 /sys/devices/virtual/sec/tsp/cmd