Make font_fallback.xml unreadable

Bug: 281769620
Test: atest CtsGraphicsTestCases
Test: atest CtsTextTestCases
Change-Id: I05011c9313fa3818ec50d9884227512ef1b0fda9
diff --git a/private/file.te b/private/file.te
index 129b1ea..64b51a2 100644
--- a/private/file.te
+++ b/private/file.te
@@ -136,3 +136,6 @@
 
 # /sys/firmware/devicetree/base/avf
 type sysfs_dt_avf, fs_type, sysfs_type;
+
+# Type for /system/fonts/font_fallback.xm
+type system_font_fallback_file, system_file_type, file_type;