Create SELinux label for contexhub_service

SELinux label is created for contexthub_service system service.

ContextHub service manages all available context hubs and serves fulfil communication between apps
and underlying context hub hardware.

Change-Id: I8470fedd9c79a00012e1cdb9b548a1b632ba7de6
diff --git a/service_contexts b/service_contexts
index 8bd4e0c..9b049e3 100644
--- a/service_contexts
+++ b/service_contexts
@@ -24,6 +24,7 @@
 connectivity                              u:object_r:connectivity_service:s0
 consumer_ir                               u:object_r:consumer_ir_service:s0
 content                                   u:object_r:content_service:s0
+contexthub_service                        u:object_r:contexthub_service:s0
 country_detector                          u:object_r:country_detector_service:s0
 cpuinfo                                   u:object_r:cpuinfo_service:s0
 dbinfo                                    u:object_r:dbinfo_service:s0