[ONOS-4520] Separate model messages from service messages in ProtoBuf IDL.

- move ProtoBuf generated code in a package similar to ONOS models.

Change-Id: I5deb591094c2b8af2b22041da935567fc8dacd87
diff --git a/incubator/rpc-grpc/src/main/proto/Link.proto b/incubator/rpc-grpc/src/main/proto/Link.proto
index 27998d3..45b9e90 100644
--- a/incubator/rpc-grpc/src/main/proto/Link.proto
+++ b/incubator/rpc-grpc/src/main/proto/Link.proto
@@ -1,5 +1,5 @@
 syntax = "proto3";
-option java_package = "org.onosproject.grpc";
+option java_package = "org.onosproject.grpc.net";
 
 package Link;
 
@@ -44,27 +44,3 @@
   LinkType type = 3;
   map<string, string> annotations = 4;
 }
-
-// Message te represent no return value
-message Void {}
-
-message LinkDetectedMsg {
-  // ProviderId scheme only
-  string provider_id = 1;
-  LinkDescription link_description = 2;
-}
-
-message LinkVanishedMsg {
-  // ProviderId scheme only
-  string provider_id = 1;
-  oneof subject {
-    LinkDescription link_description = 2;
-    ConnectPoint connect_point = 3;
-    string device_id = 4;
-  }
-}
-
-service LinkProviderServiceRpc {
-  rpc LinkDetected(LinkDetectedMsg) returns (Void);
-  rpc LinkVanished(LinkVanishedMsg) returns (Void);
-}