Updating to newer xapp-frame 0.0.30 version. Prepared also for 4.* version

Change-Id: I86866b1e57bbc84421eb365d38b62839c8954f50
Signed-off-by: Juha Hyttinen <juha.hyttinen@nokia.com>
diff --git a/pkg/xapptweaks/rmrwrapper.go b/pkg/xapptweaks/rmrwrapper.go
index 5d59363..09fa6de 100644
--- a/pkg/xapptweaks/rmrwrapper.go
+++ b/pkg/xapptweaks/rmrwrapper.go
@@ -66,8 +66,10 @@
 	}
 	if status == false {
 		err = fmt.Errorf("Failed with retries(%d) %s", i, params.String())
-		tc.Rmr.Free(params.Mbuf)
-		params.Mbuf = nil
+		if params.Mbuf != nil {
+			tc.Rmr.Free(params.Mbuf)
+			params.Mbuf = nil
+		}
 	} else {
 		tc.CntSentMsg++
 	}