arm920t/interrupts: Move conditional compilation to Makefile

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

cpu/arm920t/Makefile

@@ -26,10 +26,12 @@ include $(TOPDIR)/config.mk
 LIB	= $(obj)lib$(CPU).a
 
 START	= start.o
-COBJS	= cpu.o interrupts.o
 
-SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(COBJS) $(SOBJS))
+COBJS-y	+= cpu.o
+COBJS-$(CONFIG_USE_IRQ)	+= interrupts.o
+
+SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS-y) $(SOBJS))
 START	:= $(addprefix $(obj),$(START))
 
 all:	$(obj).depend $(START) $(LIB)

cpu/arm920t/interrupts.c

@@ -30,9 +30,8 @@
  */
 
 #include <common.h>
-
-#ifdef CONFIG_USE_IRQ
 #include <asm/proc-armv/ptrace.h>
+
 void do_irq (struct pt_regs *pt_regs)
 {
 #if defined (ARM920_IRQ_CALLBACK)
@@ -46,4 +45,3 @@ void do_irq (struct pt_regs *pt_regs)
 #error do_irq() not defined for this cpu type
 #endif
 }
-#endif