No imu fix Iron (luxonis#501)

Author: Serafadam

README.md

@@ -1,4 +1,4 @@
 # Depthai ROS Repository
 Hi and welcome to the main depthai-ros respository! Here you can find ROS related code for OAK cameras from Luxonis. Don't have one? You can get them [here!](https://shop.luxonis.com/)
 
-You can find the newest documentation [here](https://docs-beta.luxonis.com/develop/ros/depthai-ros-intro/).
+You can find the newest documentation [here](https://docs-beta.luxonis.com/software/ros/depthai-ros/intro/).

depthai_ros_driver/src/pipeline/pipeline_generator.cpp

@@ -38,7 +38,7 @@ std::vector<std::unique_ptr<dai_nodes::BaseNode>> PipelineGenerator::createPipel
     }
 
     if(enableImu) {
-        if(device->getConnectedIMU() == "NONE") {
+        if(device->getConnectedIMU() == "NONE" || device->getConnectedIMU().empty()){
             RCLCPP_WARN(node->get_logger(), "IMU enabled but not available!");
         } else {
             auto imu = std::make_unique<dai_nodes::Imu>("imu", node, pipeline, device);