Rename our 'task_spawn' to 'task_spawn_cmd' since NuttX now has its own version of task_spawn that's different.

src/modules/systemlib/systemlib.c

@@ -65,7 +65,7 @@ static void kill_task(FAR struct tcb_s *tcb, FAR void *arg)
 	kill(tcb->pid, SIGUSR1);
 }
 
-int task_spawn(const char *name, int scheduler, int priority, int stack_size, main_t entry, const char *argv[])
+int task_spawn_cmd(const char *name, int scheduler, int priority, int stack_size, main_t entry, const char *argv[])
 {
 	int pid;
 

src/modules/systemlib/systemlib.h

@@ -58,7 +58,7 @@ __EXPORT void killall(void);
 #endif
 
 /** Starts a task and performs any specific accounting, scheduler setup, etc. */
-__EXPORT int task_spawn(const char *name,
+__EXPORT int task_spawn_cmd(const char *name,
 			int priority,
 			int scheduler,
 			int stack_size,