ALSA: core: Fix assignment in if condition

There are a few places doing assignments in if condition in ALSA core
code, which is a bad coding style that may confuse readers and
occasionally lead to bugs.

This patch is merely for coding-style fixes, no functional changes.

Link: https://lore.kernel.org/r/20210608140540.17885-54-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/sound.c b/sound/core/sound.c
index af89e51..df5571d 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -357,7 +357,8 @@ static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_bu
 
 	mutex_lock(&sound_mutex);
 	for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
-		if (!(mptr = snd_minors[minor]))
+		mptr = snd_minors[minor];
+		if (!mptr)
 			continue;
 		if (mptr->card >= 0) {
 			if (mptr->device >= 0)