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/property_contexts b/private/property_contexts
index 515c007..d1a4ecf 100644
--- a/private/property_contexts
+++ b/private/property_contexts
@@ -255,6 +255,7 @@
 persist.device_config.netd_native.                  u:object_r:device_config_netd_native_prop:s0
 persist.device_config.nnapi_native.                 u:object_r:device_config_nnapi_native_prop:s0
 persist.device_config.profcollect_native_boot.      u:object_r:device_config_profcollect_native_boot_prop:s0
+persist.device_config.remote_key_provisioning_native.  u:object_r:device_config_remote_key_provisioning_native_prop:s0
 persist.device_config.runtime_native.               u:object_r:device_config_runtime_native_prop:s0
 persist.device_config.runtime_native_boot.          u:object_r:device_config_runtime_native_boot_prop:s0
 persist.device_config.statsd_native.                u:object_r:device_config_statsd_native_prop:s0