Add keyguard_config_prop for keyguard property

keyguard.no_require_sim becomes keyguard_config_prop to remove
exported*_default_prop

Bug: 155844385
Test: boot and see no denials
Change-Id: Icffa88b650a1d35d8c1cd29f89daf0644a79ddd3
diff --git a/private/property.te b/private/property.te
index 77d3dff..6f984ec 100644
--- a/private/property.te
+++ b/private/property.te
@@ -412,3 +412,8 @@
   -appdomain
   -vendor_init
 } packagemanager_config_prop:file no_rw_file_perms;
+
+neverallow {
+  -coredomain
+  -vendor_init
+} keyguard_config_prop:file no_rw_file_perms;