Add new context packagemanager_config_prop

To remove bad context names exported[23]_default_prop

Bug: 155844385
Test: m selinux_policy
Change-Id: Ic4bbc8e45d810368a96f6985c2234798e73be82d
diff --git a/private/property.te b/private/property.te
index b5505e5..6591a9c 100644
--- a/private/property.te
+++ b/private/property.te
@@ -414,3 +414,10 @@
   surfaceflinger_display_prop
 }:property_service set;
 
+neverallow {
+  -init
+  -dumpstate
+  -system_server
+  -vendor_init
+  -zygote
+} packagemanager_config_prop:file no_rw_file_perms;