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/modules/systemlib/module.mk

@@ -42,7 +42,6 @@ SRCS		 = err.c \
 		   cpuload.c \
 		   getopt_long.c \
 		   pid/pid.c \
-		   systemlib.c \
 		   airspeed.c \
 		   system_params.c \
 		   mavlink_log.c \

src/modules/systemlib/systemlib.h

@@ -42,31 +42,12 @@
 #include <float.h>
 #include <stdint.h>
 #include <sched.h>
+
+// OS specific settings defined in px4_tasks.h
 #include <px4_tasks.h>
 
 __BEGIN_DECLS
 
-/** Reboots the board */
-__EXPORT void systemreset(bool to_bootloader) noreturn_function;
-
-/** Sends SIGUSR1 to all processes */
-__EXPORT void killall(void);
-
-/** Default scheduler type */
-#if CONFIG_RR_INTERVAL > 0
-# define SCHED_DEFAULT	SCHED_RR
-#else
-# define SCHED_DEFAULT	SCHED_FIFO
-#endif
-
-/** Starts a task and performs any specific accounting, scheduler setup, etc. */
-__EXPORT int task_spawn_cmd(const char *name,
-			int priority,
-			int scheduler,
-			int stack_size,
-			px4_main_t entry,
-			char * const argv[]);
-
 enum MULT_PORTS {
 	MULT_0_US2_RXTX = 0,
 	MULT_1_US2_FLOW,