Removed extra abstracton layer in systemlib

The calls to task_spawn_cmd, kill_all, and systemreset  were wrappers
around the px4_{task_spawn_cmd|kill_all|systemreset} implementations.

Removed the wrappers and changed all calls to the px4_ equivalents.

NuttX specific code was moved into px4_tasks.h

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

src/drivers/ardrone_interface/ardrone_interface.c

@@ -121,7 +121,7 @@ int ardrone_interface_main(int argc, char *argv[])
 		}
 
 		thread_should_exit = false;
-		ardrone_interface_task = task_spawn_cmd("ardrone_interface",
+		ardrone_interface_task = px4_task_spawn_cmd("ardrone_interface",
 						    SCHED_DEFAULT,
 						    SCHED_PRIORITY_MAX - 15,
 						    1100,

src/drivers/frsky_telemetry/frsky_telemetry.c

@@ -216,7 +216,7 @@ int frsky_telemetry_main(int argc, char *argv[])
 			errx(0, "frsky_telemetry already running");
 
 		thread_should_exit = false;
-		frsky_task = task_spawn_cmd("frsky_telemetry",
+		frsky_task = px4_task_spawn_cmd("frsky_telemetry",
 					  SCHED_DEFAULT,
 					  SCHED_PRIORITY_DEFAULT,
 					  2000,

src/drivers/gps/gps.cpp

@@ -229,7 +229,7 @@ GPS::init()
 		goto out;
 
 	/* start the GPS driver worker task */
-	_task = task_spawn_cmd("gps", SCHED_DEFAULT,
+	_task = px4_task_spawn_cmd("gps", SCHED_DEFAULT,
 				SCHED_PRIORITY_SLOW_DRIVER, 1500, (main_t)&GPS::task_main_trampoline, nullptr);
 
 	if (_task < 0) {

src/drivers/hott/hott_sensors/hott_sensors.cpp

@@ -209,7 +209,7 @@ hott_sensors_main(int argc, char *argv[])
 		}
 
 		thread_should_exit = false;
-		deamon_task = task_spawn_cmd(daemon_name,
+		deamon_task = px4_task_spawn_cmd(daemon_name,
 					     SCHED_DEFAULT,
 					     SCHED_PRIORITY_DEFAULT,
 					     1024,

src/drivers/hott/hott_telemetry/hott_telemetry.cpp

@@ -235,7 +235,7 @@ hott_telemetry_main(int argc, char *argv[])
 		}
 
 		thread_should_exit = false;
-		deamon_task = task_spawn_cmd(daemon_name,
+		deamon_task = px4_task_spawn_cmd(daemon_name,
 					 SCHED_DEFAULT,
 					 SCHED_PRIORITY_DEFAULT,
 					 2048,

src/drivers/md25/md25_main.cpp

@@ -110,7 +110,7 @@ int md25_main(int argc, char *argv[])
 		}
 
 		thread_should_exit = false;
-		deamon_task = task_spawn_cmd("md25",
+		deamon_task = px4_task_spawn_cmd("md25",
 					 SCHED_DEFAULT,
 					 SCHED_PRIORITY_MAX - 10,
 					 2048,

src/drivers/mkblctrl/mkblctrl.cpp

@@ -302,7 +302,7 @@ MK::init(unsigned motors)
 	}
 
 	/* start the IO interface task */
-	_task = task_spawn_cmd("mkblctrl",
+	_task = px4_task_spawn_cmd("mkblctrl",
 			       SCHED_DEFAULT,
 			       SCHED_PRIORITY_MAX - 20,
 			       1500,

src/drivers/px4fmu/fmu.cpp

@@ -341,7 +341,7 @@ PX4FMU::init()
 	gpio_reset();
 
 	/* start the IO interface task */
-	_task = task_spawn_cmd("fmuservo",
+	_task = px4_task_spawn_cmd("fmuservo",
 			       SCHED_DEFAULT,
 			       SCHED_PRIORITY_DEFAULT,
 			       1600,

src/drivers/px4io/px4io.cpp

@@ -854,7 +854,7 @@ PX4IO::init()
 	}
 
 	/* start the IO interface task */
-	_task = task_spawn_cmd("px4io",
+	_task = px4_task_spawn_cmd("px4io",
 					SCHED_DEFAULT,
 					SCHED_PRIORITY_ACTUATOR_OUTPUTS,
 					1800,

src/drivers/roboclaw/roboclaw_main.cpp

@@ -105,7 +105,7 @@ int roboclaw_main(int argc, char *argv[])
 		}
 
 		thread_should_exit = false;
-		deamon_task = task_spawn_cmd("roboclaw",
+		deamon_task = px4_task_spawn_cmd("roboclaw",
 					 SCHED_DEFAULT,
 					 SCHED_PRIORITY_MAX - 10,
 					 2048,