Update sitl_run to check for -gen.sdf files (#15232)

Co-authored-by: Anton Erasmus <antonerasm@gmail.com>

Tools/sitl_run.sh

@@ -80,6 +80,13 @@ if [ "$program" == "jmavsim" ] && [ ! -n "$no_sim" ]; then
 	SIM_PID=`echo $!`
 elif [ "$program" == "gazebo" ] && [ ! -n "$no_sim" ]; then
 	if [ -x "$(command -v gazebo)" ]; then
+		# Get the model name
+		model_name="${model}"
+		# Check if a 'modelname-gen.sdf' file exist for the models using jinja and generating the SDF files
+		if [ -f "${src_path}/Tools/sitl_gazebo/models/${model}/${model}-gen.sdf" ]; then
+			model_name="${model}-gen"
+		fi
+
 		# Set the plugin path so Gazebo finds our model and sim
 		source "$src_path/Tools/setup_gazebo.bash" "${src_path}" "${build_path}"
 		if [ -z $PX4_SITL_WORLD ]; then
@@ -107,7 +114,7 @@ elif [ "$program" == "gazebo" ] && [ ! -n "$no_sim" ]; then
 		fi
 		SIM_PID=$!
 
-		while gz model --verbose --spawn-file="${src_path}/Tools/sitl_gazebo/models/${model}/${model}.sdf" --model-name=${model} -x 1.01 -y 0.98 -z 0.83 2>&1 | grep -q "An instance of Gazebo is not running."; do
+		while gz model --verbose --spawn-file="${src_path}/Tools/sitl_gazebo/models/${model}/${model_name}.sdf" --model-name=${model} -x 1.01 -y 0.98 -z 0.83 2>&1 | grep -q "An instance of Gazebo is not running."; do
 			echo "gzserver not ready yet, trying again!"
 			sleep 1
 		done