AP_Compass: removed spurious rotation in PX4 backend

and cleanup rotation macros

libraries/AP_Compass/AP_Compass_PX4.cpp

@@ -119,10 +119,6 @@ void AP_Compass_PX4::read(void)
         _sum[i] /= _count[i];
         _sum[i] *= 1000;
 
-        // apply default board orientation for this compass type. This is
-        // a noop on most boards
-        _sum[i].rotate(MAG_BOARD_ORIENTATION);
-
         publish_field(_sum[i], _instance[i]);
     
         _sum[i].zero();

libraries/AP_Compass/Compass.h

@@ -24,27 +24,11 @@
 #define AP_COMPASS_MOT_COMP_THROTTLE    0x01
 #define AP_COMPASS_MOT_COMP_CURRENT     0x02
 
-// setup default mag orientation for each board type
+// setup default mag orientation for some board types
 #if CONFIG_HAL_BOARD == HAL_BOARD_APM1
 # define MAG_BOARD_ORIENTATION ROTATION_ROLL_180
-#elif CONFIG_HAL_BOARD == HAL_BOARD_APM2
-# define MAG_BOARD_ORIENTATION ROTATION_NONE
-#elif CONFIG_HAL_BOARD == HAL_BOARD_FLYMAPLE
-# define MAG_BOARD_ORIENTATION ROTATION_NONE
-#elif CONFIG_HAL_BOARD == HAL_BOARD_PX4
-# define MAG_BOARD_ORIENTATION ROTATION_NONE
-#elif CONFIG_HAL_BOARD == HAL_BOARD_AVR_SITL
-# define MAG_BOARD_ORIENTATION ROTATION_NONE
-#elif CONFIG_HAL_BOARD == HAL_BOARD_LINUX
-    #if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_NAVIO
-    # define MAG_BOARD_ORIENTATION ROTATION_NONE
-    #else
-    # define MAG_BOARD_ORIENTATION ROTATION_NONE
-    #endif
-#elif CONFIG_HAL_BOARD == HAL_BOARD_VRBRAIN
-# define MAG_BOARD_ORIENTATION ROTATION_NONE
 #else
-# error "You must define a default compass orientation for this board"
+# define MAG_BOARD_ORIENTATION ROTATION_NONE
 #endif
 
 /**