resource: fix memory leaks in resource moodule

Problem: The resource module leaks a struct rlist and an R object
when loading R from configuration.

Free the intermediate rlist in convert_R_conf(), and the "R_from_config"
after it is added to the inventory.

Author: grondo

src/modules/resource/inventory.c

@@ -280,6 +280,7 @@ static int convert_R_conf (flux_t *h, json_t *conf_R, json_t **Rp)
         errno = ENOMEM;
         goto error;
     }
+    rlist_destroy (rl);
     *Rp = R;
     return 0;
 error:

src/modules/resource/resource.c

@@ -437,6 +437,9 @@ int mod_main (flux_t *h, int argc, char **argv)
     }
     if (!(ctx->inventory = inventory_create (ctx, R_from_config)))
         goto error;
+    /*  Done with R_from_config now, so free it.
+     */
+    json_decref (R_from_config);
     if (!(ctx->topology = topo_create (ctx, noverify, norestrict)))
         goto error;
     if (!(ctx->monitor = monitor_create (ctx, monitor_force_up)))