Keep track of go version

src/freedombone-utils-go

@@ -197,10 +197,14 @@ function upgrade_golang {
         return
     fi
 
+    if ! grep -Fxq "upgrade_golang:$GO_VERSION" $COMPLETION_FILE; then
+        return
+    fi
+
     rootdir=
     mesh_upgrade_golang
 
-    echo 'upgrade_golang' >> $COMPLETION_FILE
+    echo "upgrade_golang:$GO_VERSION" >> $COMPLETION_FILE
 }
 
 # NOTE: deliberately there is no "exit 0"