Refactor of UpfProgrammable APIs

Change-Id: I792659ad4a163d7115d7320bb33c11534edd484a
Signed-off-by: Daniele Moro <daniele@opennetworking.org>
(cherry picked from commit a57652d92bdd01b1e77bffbac78a44f96fb385f3)
diff --git a/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfProgrammable.java b/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfProgrammable.java
index 159adb0..052084e 100644
--- a/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfProgrammable.java
+++ b/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfProgrammable.java
@@ -30,13 +30,12 @@
 public interface UpfProgrammable extends HandlerBehaviour, UpfDevice {
     /**
      * Apps are expected to call this method as the first one when they are ready
-     * to install PDRs and FARs.
+     * to install any UPF entity.
      *
      * @return True if initialized, false otherwise.
      */
     boolean init();
 
-
     /**
      * Checks if the given flow rule has been generated by this UPF behaviour.
      *