Decompile librfu_intr against agbcc_arm

Makefile

@@ -173,6 +173,9 @@ $(C_BUILDDIR)/isagbprn.o: CFLAGS := -mthumb-interwork
 $(C_BUILDDIR)/trainer_tower.o: CFLAGS += -ffreestanding
 $(C_BUILDDIR)/flying.o: CFLAGS += -ffreestanding
 
+$(C_BUILDDIR)/librfu_intr.o: CC1 := tools/agbcc/bin/agbcc_arm
+$(C_BUILDDIR)/librfu_intr.o: CFLAGS := -O2 -mthumb-interwork -quiet
+
 ifeq ($(NODEP),1)
 $(C_BUILDDIR)/%.o: c_dep :=
 else