ALSA: hda - Warn an allocation for an uninitialized array

Better to add a sanity check as I tend to forget something (especially
during crazy midsummer nights).

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index c0ab72c..70d4848 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -5168,6 +5168,8 @@
  */
 void *snd_array_new(struct snd_array *array)
 {
+	if (snd_BUG_ON(!array->elem_size))
+		return NULL;
 	if (array->used >= array->alloced) {
 		int num = array->alloced + array->alloc_align;
 		int size = (num + 1) * array->elem_size;