ALSA: core: timer: Use NSEC_PER_SEC macro

1000000000L is number of ns per second, use NSEC_PER_SEC macro to replace
it to make it more readable
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Link: https://patch.msgid.link/20240902071622.3519787-1-ruanjinjie@huawei.comSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/timer.c

@@ -1174,7 +1174,7 @@ static int snd_timer_s_close(struct snd_timer *timer)
 static const struct snd_timer_hardware snd_timer_system =
 {
 	.flags =	SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_WORK,
-	.resolution =	1000000000L / HZ,
+	.resolution =	NSEC_PER_SEC / HZ,
 	.ticks =	10000000L,
 	.close =	snd_timer_s_close,
 	.start =	snd_timer_s_start,