cmake remove circular linking and reorganize

- px4_add_module now requires MAIN
 - px4_add_library doesn't automatically link

src/drivers/differential_pressure/ms4525/CMakeLists.txt

@@ -38,6 +38,5 @@ px4_add_module(
 	SRCS
 		ms4525_airspeed.cpp
 	DEPENDS
-		platforms__common
+		drivers__airspeed
 	)
-# vim: set noet ft=cmake fenc=utf-8 ff=unix :

src/drivers/differential_pressure/ms4525/ms4525_airspeed.cpp

@@ -55,8 +55,8 @@
 
 #include <systemlib/airspeed.h>
 #include <systemlib/err.h>
-#include <systemlib/param/param.h>
-#include <systemlib/perf_counter.h>
+#include <parameters/param.h>
+#include <perf/perf_counter.h>
 
 #include <mathlib/math/filter/LowPassFilter2p.hpp>