Flow mockup (#14054)

* Add optical flow mockup model

* Update Tools.sitl_gazebo

ROMFS/px4fmu_common/init.d-posix/1017_iris_opt_flow_mockup

@@ -0,0 +1,21 @@
+#!/bin/sh
+#
+# @name 3DR Iris Quadrotor SITL (Optical Flow)
+#
+# @type Quadrotor Wide
+#
+
+sh /etc/init.d-posix/10016_iris
+
+if [ $AUTOCNF = yes ]
+then
+	# EKF2
+	param set EKF2_AID_MASK 2
+	param set SENS_FLOW_ROT 0
+
+	# LPE: Flow-only mode
+	param set LPE_FUSION 242
+	param set LPE_FAKE_ORIGIN 1
+
+	param set MPC_ALT_MODE 2
+fi