[MTD] [NAND] S3C2410: Use DIV_ROUND_UP

Change to using DIV_ROUND_UP() in the timing calculation
instead of blindly doing result++

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

drivers/mtd/nand/s3c2410.c

@@ -180,8 +180,7 @@ static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
 {
 	int result;
 
-	result = (wanted * clk) / NS_IN_KHZ;
-	result++;
+	result = DIV_ROUND_UP((wanted * clk), NS_IN_KHZ);
 
 	pr_debug("result %d from %ld, %d\n", result, clk, wanted);