arch/m32r: Use DIV_ROUND_CLOSEST

The kernel.h macro DIV_ROUND_CLOSEST performs the computation (x + d/2)/d
but is perhaps more readable.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

@depends on haskernel@
expression x,__divisor;
@@

- (((x) + ((__divisor) / 2)) / (__divisor))
+ DIV_ROUND_CLOSEST(x,__divisor)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>

arch/m32r/kernel/time.c

@@ -75,7 +75,7 @@ u32 arch_gettimeoffset(void)
 		count = 0;
 
 	count = (latch - count) * TICK_SIZE;
-	elapsed_time = (count + latch / 2) / latch;
+	elapsed_time = DIV_ROUND_CLOSEST(count, latch);
 	/* NOTE: LATCH is equal to the "interval" value (= reload count). */
 
 #else /* CONFIG_SMP */
@@ -93,7 +93,7 @@ u32 arch_gettimeoffset(void)
 	p_count = count;
 
 	count = (latch - count) * TICK_SIZE;
-	elapsed_time = (count + latch / 2) / latch;
+	elapsed_time = DIV_ROUND_CLOSEST(count, latch);
 	/* NOTE: LATCH is equal to the "interval" value (= reload count). */
 #endif /* CONFIG_SMP */
 #elif defined(CONFIG_CHIP_M32310)
@@ -211,7 +211,7 @@ void __init time_init(void)
 
 		bus_clock = boot_cpu_data.bus_clock;
 		divide = boot_cpu_data.timer_divide;
-		latch = (bus_clock/divide + HZ / 2) / HZ;
+		latch = DIV_ROUND_CLOSEST(bus_clock/divide, HZ);
 
 		printk("Timer start : latch = %ld\n", latch);