mqarender: allow specifying target rate as multiple of input rate

mqarender.c

@@ -106,6 +106,8 @@ int main(int argc, char **argv)
 
 	if (!rate2)
 		rate2 = 2 * rate1;
+	else if (rate2 <= 32)
+		rate2 = rate1 * rate2;
 
 	if (rate2 % rate1) {
 		fprintf(stderr, "Output rate must be multiple of input rate\n");