[fix][fixedwing] init state interface _before_ sensors and ins

This had the very very nasty effect that the local coordinate system was not initialized
if NavSetGroundReferenceHere() was not called from the fliht plan,
(e.g. because not waitinf for GeoInit to finish).

sw/airborne/firmwares/fixedwing/main_ap.c

@@ -155,6 +155,10 @@ void init_ap( void ) {
   mcu_init();
 #endif /* SINGLE_MCU */
 
+  /****** initialize and reset state interface ********/
+
+  stateInit();
+
   /************* Sensors initialization ***************/
 #if USE_GPS
   gps_init();
@@ -178,8 +182,6 @@ void init_ap( void ) {
 
   ins_init();
 
-  stateInit();
-
   /************* Links initialization ***************/
 #if defined MCU_SPI_LINK || defined MCU_UART_LINK
   link_mcu_init();