Allow bluetooth access to keystore service.

Address the following denial:
SELinux : avc:  denied  { find } for service=android.security.keystore scontext=u:r:bluetooth:s0 tcontext=u:object_r:keystore_service:s0 tclass=service_manager

Encountered when remote service attempts access:
02-04 00:15:19.174 E/AndroidRuntime(10847): FATAL EXCEPTION: main
02-04 00:15:19.174 E/AndroidRuntime(10847): Process: com.google.android.remote.tv.services, PID: 10847
02-04 00:15:19.174 E/AndroidRuntime(10847): java.lang.RuntimeException: Unable to create service com.google.android.tv.remote.RemoteService: java.lang.NullPointerException: Attempt to invoke interface method 'int android.security.IKeystoreService.exist(java.lang.String, int)' on a null object reference
02-04 00:15:19.174 E/AndroidRuntime(10847):         at android.app.ActivityThread.handleCreateService(ActivityThread.java:2801)

Bug: 19268019
Change-Id: I86f85cb19c5540bf041c82ec9a8088aacae67792

bluetooth.te

@@ -50,6 +50,7 @@ allow bluetooth pan_result_prop:property_service set;
 allow bluetooth ctl_dhcp_pan_prop:property_service set;
 
 allow bluetooth bluetooth_service:service_manager find;
+allow bluetooth keystore_service:service_manager find;
 allow bluetooth radio_service:service_manager find;
 allow bluetooth system_server_service:service_manager find;
 allow bluetooth tmp_system_server_service:service_manager find;