sepolicy: Allow system app to set boot anim property

Addresses denials observerd when using QuickBoot:

<4>[  224.756971] avc:  denied  { set } for property=ctl.bootanim scontext=u:r:system_app:s0 tcontext=u:object_r:ctl_bootanim_prop:s0 tclass=property_service
<3>[  224.757094] init: sys_prop: Unable to start service ctl [bootanim] uid:1000 gid:1000 pid:6039
<4>[  226.306456] avc:  denied  { set } for property=ctl.bootanim scontext=u:r:system_app:s0 tcontext=u:object_r:ctl_bootanim_prop:s0 tclass=property_service

Change-Id: I338a0a1d5fa12c10e413769ea9638c10ed137000
diff --git a/sepolicy/system_app.te b/sepolicy/system_app.te
index 9dbc7b8..be2fb2f 100644
--- a/sepolicy/system_app.te
+++ b/sepolicy/system_app.te
@@ -3,3 +3,6 @@
 allow system_app recovery_cache_file:file create_file_perms;
 allow system_app media_rw_data_file:dir create_dir_perms;
 allow system_app media_rw_data_file:file create_file_perms;
+
+# Boot animation
+allow system_app ctl_bootanim_prop:property_service set;