Fix all warnings raised by IDO (#152)

* Fix all warnings raised by IDO, ignore trailing commas

* Set -woff=624,...; keep const in printf functions

* Remove redefined macros in irqmgr.c

* Remove DECR macro & reformat

* Address PR comments from AngheloAlf

include/z64effect.h

@@ -9,6 +9,7 @@
 
 struct GraphicsContext;
 struct GlobalContext;
+struct EffectSs;
 
 typedef void(*eff_destroy_func)(void* params);