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/s3c44b0/Makefile b/cpu/s3c44b0/Makefile
index ae909a6..6da2016 100644
--- a/cpu/s3c44b0/Makefile
+++ b/cpu/s3c44b0/Makefile
@@ -26,7 +26,10 @@
 LIB	= $(obj)lib$(CPU).a
 
 START	= start.o
-COBJS	= cache.o cpu.o interrupts.o
+
+COBJS	+= cache.o
+COBJS	+= cpu.o
+COBJS	+= timer.o
 
 SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
 OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))
diff --git a/cpu/s3c44b0/interrupts.c b/cpu/s3c44b0/timer.c
similarity index 98%
rename from cpu/s3c44b0/interrupts.c
rename to cpu/s3c44b0/timer.c
index eb23e6a..34184ab 100644
--- a/cpu/s3c44b0/interrupts.c
+++ b/cpu/s3c44b0/timer.c
@@ -40,7 +40,7 @@
 static ulong timestamp;
 static ulong lastdec;
 
-int interrupt_init (void)
+int timer_init (void)
 {
 	TCFG0 = 0x000000E9;
 	TCFG1 = 0x00000004;