Let system server set permissions on marker file

System server needs to create a file in /metadata/aconfig, and set its
permissions.

Bug: 328444881
Test: m
Change-Id: I30aa576e46d8963e78ff21ad328160a99bd5d523
diff --git a/private/file.te b/private/file.te
index 5295f69..b96e18b 100644
--- a/private/file.te
+++ b/private/file.te
@@ -156,6 +156,8 @@
 # Type for /vendor/etc/aconfig
 type vendor_aconfig_storage_file, vendor_file_type, file_type;
 
+type aconfig_test_mission_files, file_type;
+
 # /data/misc/connectivityblobdb
 type connectivityblob_data_file, file_type, data_file_type, core_data_file_type;