Add SELinux policies for remote_key_provisioning_native namespace.

We need to separate out the feature flags in use by remote key
provisioning daemon (RKPD). For this, I have set up a new namespace
remote_key_provisioning_native. This change adds the SELinux policies to
make sure appropriate permissions are present when accessing the feature
flag for read/write.

Change-Id: I9e73a623f847a058b6236dd0aa370a7f9a9e6da7
Test: TreeHugger
diff --git a/private/keystore.te b/private/keystore.te
index 8e681b1..b69477c 100644
--- a/private/keystore.te
+++ b/private/keystore.te
@@ -20,6 +20,9 @@
 # Allow keystore to check if the system is rkp only.
 get_prop(keystore, remote_prov_prop)
 
+# Allow keystore to check rkpd feature flags
+get_prop(keystore, device_config_remote_key_provisioning_native_prop)
+
 # Allow keystore to write to statsd.
 unix_socket_send(keystore, statsdw, statsd)