fix(nimble): Address compilation issues in nimble examples

examples/bluetooth/nimble/ble_dynamic_service/main/main.c

@@ -280,12 +280,14 @@ app_main(void)
     ble_hs_cfg.gatts_register_cb = gatt_svr_register_cb;
     ble_hs_cfg.store_status_cb = ble_store_util_status_rr;
 
+#if MYNEWT_VAL(BLE_GATTS)
     rc = gatt_svr_init();
     assert(rc == 0);
 
     /* Set the default device name. */
     rc = ble_svc_gap_device_name_set("ble-dynamic-service");
     assert(rc == 0);
+#endif
 
     nimble_port_freertos_init(dynamic_service_host_task);