Remove main.c's dependency on mw.h/board.h.

Moved pidControllers out of mw.c into flight_common.c/h.
Moved appropriate code into rc_controls.c/h.

src/rc_controls.c

@@ -0,0 +1,15 @@
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <math.h>
+
+#include "common/maths.h"
+
+#include "rc_controls.h"
+
+int16_t rcCommand[4];           // interval [1000;2000] for THROTTLE and [-500;+500] for ROLL/PITCH/YAW
+
+bool areSticksInApModePosition(uint16_t ap_mode)
+{
+    return abs(rcCommand[ROLL]) < ap_mode && abs(rcCommand[PITCH]) < ap_mode;
+}