added more mastership-related interfaces

Change-Id: I3c5da1e2a4346d6e557232c5f896b32a7268ec39
diff --git a/core/api/src/main/java/org/onlab/onos/net/device/DeviceAdminService.java b/core/api/src/main/java/org/onlab/onos/net/device/DeviceAdminService.java
index 8aec28a..23856ab 100644
--- a/core/api/src/main/java/org/onlab/onos/net/device/DeviceAdminService.java
+++ b/core/api/src/main/java/org/onlab/onos/net/device/DeviceAdminService.java
@@ -13,7 +13,9 @@
      *
      * @param deviceId device identifier
      * @param role     requested role
+     * @deprecated Will be removed in favor of MastershipAdminService.setRole()
      */
+    @Deprecated
     void setRole(DeviceId deviceId, MastershipRole role);
 
     /**