Fixed non-static struct initializers.

tests/mini/structinit3.d

@@ -0,0 +1,13 @@
+struct S {
+    int a; int b; int c; int d = 7;
+}
+void test(int i) {
+    S s = { 1, i };   // q.a = 1, q.b = i, q.c = 0, q.d = 7
+    assert(s.a == 1);
+    assert(s.b == i);
+    assert(s.c == 0); // line 8
+    assert(s.d == 7);
+}
+void main() {
+    test(42);
+}