delete px4_includes.h header and update boards/ to use syslog

src/drivers/snapdragon_pwm_out/snapdragon_pwm_out.cpp

@@ -38,7 +38,7 @@
 #include <px4_posix.h>
 #include <errno.h>
 #include <cmath>	// NAN
-
+#include <string.h>
 
 #include <uORB/uORB.h>
 #include <uORB/topics/actuator_controls.h>
@@ -505,8 +505,6 @@ void task_main_trampoline(int argc, char *argv[])
 
 void start()
 {
-	ASSERT(_task_handle == -1);
-
 	_task_should_exit = false;
 
 	/* start the task */
@@ -518,7 +516,7 @@ void start()
 					  nullptr);
 
 	if (_task_handle < 0) {
-		warn("task start failed");
+		PX4_ERR("task start failed");
 		return;
 	}