Reduce excessive stack sizes for FW estimation / control apps

src/modules/ekf_att_pos_estimator/ekf_att_pos_estimator_main.cpp

@@ -1533,7 +1533,7 @@ FixedwingEstimator::start()
 	_estimator_task = task_spawn_cmd("ekf_att_pos_estimator",
 					 SCHED_DEFAULT,
 					 SCHED_PRIORITY_MAX - 40,
-					 6000,
+					 5000,
 					 (main_t)&FixedwingEstimator::task_main_trampoline,
 					 nullptr);
 

src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp

@@ -1449,7 +1449,7 @@ FixedwingPositionControl::start()
 	_control_task = task_spawn_cmd("fw_pos_control_l1",
 				       SCHED_DEFAULT,
 				       SCHED_PRIORITY_MAX - 5,
-				       4048,
+				       3500,
 				       (main_t)&FixedwingPositionControl::task_main_trampoline,
 				       nullptr);