ALSA: spi: Drop superfluous PCM preallocation error checks

snd_pcm_lib_preallocate_pages() and co always succeed, so the error
check is simply redundant.  Drop it.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/spi/at73c213.c

@@ -350,7 +350,7 @@ static int snd_at73c213_pcm_new(struct snd_at73c213 *chip, int device)
 
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &at73c213_playback_ops);
 
-	retval = snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
+	snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
 			SNDRV_DMA_TYPE_DEV, &chip->ssc->pdev->dev,
 			64 * 1024, 64 * 1024);
 out: