Increasing the rpc timeouts of olt adapter so that the grpc retries wont be exhausted by the time voltha core recovers from a crash

Change-Id: Ib6f58fe01046ddcb8ce71f89faa2351bae9b487e
diff --git a/voltha-adapter-openolt/values.yaml b/voltha-adapter-openolt/values.yaml
index 28d8bfa..08e6010 100644
--- a/voltha-adapter-openolt/values.yaml
+++ b/voltha-adapter-openolt/values.yaml
@@ -26,14 +26,14 @@
   image_pullPolicy: "Always"
   core_endpoint: "{{ .Values.global.voltha_release_name }}-{{ .Values.global.stack_name }}-core.{{ .Release.Namespace }}.svc:55558"
   # timeout for RPC request
-  rpc_timeout: "10s"
+  rpc_timeout: "20s"
   adapter_open_olt:
     timeout: "5s"
     heartbeat_check_interval: "15s"
     heartbeat_fail_interval: "31s"
     check_onu_exist_on_discovery: false
-    per_rpc_retry_timeout : "2s"
-    rpc_retry: "5"
+    per_rpc_retry_timeout : "5s"
+    rpc_retry: "4"
   # enable OMCC encryption
   omcc_encryption: false
   # enable ONU stats