leds: tca6507: use swap() to make code cleaner

Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid
opencoding it.

Signed-off-by: Yihao Han <hanyihao@vivo.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
diff --git a/drivers/leds/leds-tca6507.c b/drivers/leds/leds-tca6507.c
index 225b7658..de8eed9 100644
--- a/drivers/leds/leds-tca6507.c
+++ b/drivers/leds/leds-tca6507.c
@@ -242,9 +242,7 @@ static int choose_times(int msec, int *c1p, int *c2p)
 	if (diff < 65536) {
 		int actual;
 		if (msec & 1) {
-			c1 = *c2p;
-			*c2p = *c1p;
-			*c1p = c1;
+			swap(*c2p, *c1p);
 		}
 		actual = time_codes[*c1p] + time_codes[*c2p];
 		if (*c1p < *c2p)