[VOL-936] add changes for onu distance proto

Change-Id: Iedc44ff0c1c26a7d3623d4b7d96bb2d425d5d24f
diff --git a/protos/voltha_protos/common.proto b/protos/voltha_protos/common.proto
index 6ca156c..91e1fb1 100644
--- a/protos/voltha_protos/common.proto
+++ b/protos/voltha_protos/common.proto
@@ -96,3 +96,28 @@
     // Additional Info
     string additional_info = 2;
 }
+message ValueType {
+        enum Type {
+                EMPTY = 0;
+                DISTANCE = 1;
+        }
+}
+message ValueSpecifier {
+	string id = 1;
+	ValueType.Type value = 2;
+}
+
+message ReturnValues {
+        uint32  Set = 1;       // Specifies what values are
+                               // set/valid in return
+
+        uint32 Unsupported = 2; // Specifies requested values not
+                                // supported by the device
+
+        uint32 Error  = 3;      // Specifies requested values not
+                                // fetched because of error
+
+        uint32 Distance = 4;    // Value of distance Set includes
+                                // DISTANCE
+
+}