support multi-dimensional instances

test/basic/instance_array.v

@@ -0,0 +1,14 @@
+module Example;
+    parameter FOO = 1;
+    initial $display("%0d", FOO);
+endmodule
+
+module top;
+    Example e[5:0]();
+    defparam e[0].FOO = 1;
+    defparam e[1].FOO = 2;
+    defparam e[2].FOO = 4;
+    defparam e[3].FOO = 8;
+    defparam e[4].FOO = 16;
+    defparam e[5].FOO = 32;
+endmodule