audio: eq_iir: Clear lookup tail with memset

Use memset() to zero the unused tail of the response lookup array in
eq_iir_walk_config() instead of a per-slot loop. The walk pre-clears
the whole table once when a lookup is requested and then fills the
in-use entries.

Signed-off-by: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>

Author: singalsu

src/audio/eq_iir/eq_iir_generic.c

@@ -270,17 +270,16 @@ static int eq_iir_walk_config(struct comp_dev *dev,
 
 	j = 0;
 	coef_data = ASSUME_ALIGNED(&config->data[config->channels_in_config], 4);
+	if (lookup)
+		memset(lookup, 0, SOF_EQ_IIR_MAX_RESPONSES * sizeof(*lookup));
+
 	for (i = 0; i < config->number_of_responses; i++) {
 		ret = eq_iir_init_response(dev, i, coef_data, coef_words_max, &j, &eq);
 		if (ret < 0)
 			return ret;
 		if (lookup)
 			lookup[i] = eq;
 	}
-	if (lookup) {
-		for (; i < SOF_EQ_IIR_MAX_RESPONSES; i++)
-			lookup[i] = NULL;
-	}
 
 	return 0;
 }