ALSA: pci/korg1212: completely remove 'set but not used' warnings

Commit 6cdc01eb ("ALSA: pci/korg1212: remove 'set but not used'
warnings") missed one __maybe_unused, add to enable make W=1 sound/
compilation with x86_64 allmodconfig
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210804185442.274057-1-pierre-louis.bossart@linux.intel.comSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/korg1212/korg1212.c

@@ -2094,7 +2094,7 @@ static int snd_korg1212_create(struct snd_card *card, struct pci_dev *pci)
 {
         int err, rc;
         unsigned int i;
-	unsigned iomem_size;
+	__maybe_unused unsigned iomem_size;
 	__maybe_unused unsigned ioport_size;
 	__maybe_unused unsigned iomem2_size;
 	struct snd_korg1212 *korg1212 = card->private_data;