VOL-1643 Unsuitable attribute names are renamed for gRPC Java support

- proto files are modified to support compilation of generated Java code
- schema.proto and yang_options.proto files are deleted since there is no need for netconf in Voltha.
Change-Id: I6d8796d74a284529e5bc5926762e77ceaa31638b
diff --git a/protos/voltha_protos/omci_mib_db.proto b/protos/voltha_protos/omci_mib_db.proto
index 4ee0638..9c3c48c 100644
--- a/protos/voltha_protos/omci_mib_db.proto
+++ b/protos/voltha_protos/omci_mib_db.proto
@@ -15,7 +15,8 @@
 //
 syntax = "proto3";
 
-option go_package = "github.com/opencord/voltha-protos/v2/go/omci";
+option go_package = "github.com/opencord/voltha-protos/v3/go/omci";
+option java_package = "org.opencord.voltha.omci";
 
 package omci;
 
@@ -67,13 +68,13 @@
 }
 
 message OpenOmciEventType {
-    enum OpenOmciEventType {
+    enum Types {
         state_change = 0; // A state machine has transitioned to a new state
     }
 }
 
 message OpenOmciEvent {
-    OpenOmciEventType.OpenOmciEventType type = 1;
+    OpenOmciEventType.Types type = 1;
 
     string data = 2; // associated data, in json format
 }