ALSA: ens1370: Use DIV_ROUND_CLOSEST() instead of open-coding it

Use DIV_ROUND_CLOSEST() instead of open-coding it. This documents intent
and makes it more clear what is going on for the casual reviewer.

Generated using the following the Coccinelle semantic patch.

// <smpl>
@r1@
expression x;
constant C1;
constant C2;
@@
 ((x) + C1) / C2

@script:python@
C1 << r1.C1;
C2 << r1.C2;
@@
try:
	if int(C1) * 2 != int(C2):
		cocci.include_match(False)
except:
	cocci.include_match(False)

@@
expression r1.x;
constant r1.C1;
constant r1.C2;
@@
-(((x) + C1) / C2)
+DIV_ROUND_CLOSEST(x, C2)
// </smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20201223172229.781-16-lars@metafoo.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/ens1370.c

@@ -752,7 +752,7 @@ static void snd_es1371_dac1_rate(struct ensoniq * ensoniq, unsigned int rate)
 	unsigned int freq, r;
 
 	mutex_lock(&ensoniq->src_mutex);
-	freq = ((rate << 15) + 1500) / 3000;
+	freq = DIV_ROUND_CLOSEST(rate << 15, 3000);
 	r = (snd_es1371_wait_src_ready(ensoniq) & (ES_1371_SRC_DISABLE |
 						   ES_1371_DIS_P2 | ES_1371_DIS_R1)) |
 		ES_1371_DIS_P1;
@@ -773,7 +773,7 @@ static void snd_es1371_dac2_rate(struct ensoniq * ensoniq, unsigned int rate)
 	unsigned int freq, r;
 
 	mutex_lock(&ensoniq->src_mutex);
-	freq = ((rate << 15) + 1500) / 3000;
+	freq = DIV_ROUND_CLOSEST(rate << 15, 3000);
 	r = (snd_es1371_wait_src_ready(ensoniq) & (ES_1371_SRC_DISABLE |
 						   ES_1371_DIS_P1 | ES_1371_DIS_R1)) |
 		ES_1371_DIS_P2;