arm: timer and interrupt init rework

actually the timer init use the interrupt_init as init callback
which make the interrupt and timer implementation difficult to follow

so now rename it as int timer_init(void) and use interrupt_init for interrupt

btw also remane the corresponding file to the functionnality implemented

as ixp arch implement two timer - one based on interrupt - so all the timer
related code is moved to timer.c

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/cpu/arm1136/omap24xx/Makefile b/cpu/arm1136/omap24xx/Makefile
index f9afed7..2a79d9b 100644
--- a/cpu/arm1136/omap24xx/Makefile
+++ b/cpu/arm1136/omap24xx/Makefile
@@ -25,9 +25,10 @@
 
 LIB	= $(obj)lib$(SOC).a
 
-COBJS	= interrupts.o
 SOBJS	= start.o
 
+COBJS	= timer.o
+
 SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
 OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))
 
diff --git a/cpu/arm1136/omap24xx/interrupts.c b/cpu/arm1136/omap24xx/timer.c
similarity index 97%
rename from cpu/arm1136/omap24xx/interrupts.c
rename to cpu/arm1136/omap24xx/timer.c
index a0c535d..8dd8d7b 100644
--- a/cpu/arm1136/omap24xx/interrupts.c
+++ b/cpu/arm1136/omap24xx/timer.c
@@ -42,8 +42,7 @@
 static ulong timestamp;
 static ulong lastinc;
 
-/* nothing really to do with interrupts, just starts up a counter. */
-int interrupt_init (void)
+int timer_init (void)
 {
 	int32_t val;