Document field_door code

include/field_door.h

@@ -3,11 +3,11 @@
 
 #include "global.h"
 
-void FieldSetDoorOpened(u32, u32);
-void FieldSetDoorClosed(u32, u32);
-s8 FieldAnimateDoorClose(u32, u32);
-s8 FieldAnimateDoorOpen(u32, u32);
+void FieldSetDoorOpened(int x, int y);
+void FieldSetDoorClosed(int x, int y);
+s8 FieldAnimateDoorClose(int x, int y);
+s8 FieldAnimateDoorOpen(int x, int y);
 bool8 FieldIsDoorAnimationRunning(void);
-u32 GetDoorSoundEffect(u32 x, u32 y);
+u16 GetDoorSoundEffect(int x, int y);
 
 #endif