Fix returning enum structs not working.

Bug: issue #1012
Test: new test case

compiler/code-generator.cpp

@@ -1403,7 +1403,7 @@ CodeGenerator::EmitReturnStmt(ReturnStmt* stmt)
         EmitExpr(stmt->expr());
 
         const auto& v = stmt->expr()->val();
-        if (v.type()->isArray())
+        if (v.type()->isArray() || v.type()->isEnumStruct())
             EmitReturnArrayStmt(stmt);
     } else {
         /* this return statement contains no expression */

tests/enum-structs/return-enum-struct.out

@@ -0,0 +1,20 @@
+First Struct
+1
+1.000000
+Hello
+1
+1.000000
+Hello
+1
+1.000000
+Hello
+New Struct Below
+1
+1.000000
+Hello
+1
+1.000000
+Hello
+1
+1.000000
+Hello

tests/enum-structs/return-enum-struct.sp

@@ -0,0 +1,45 @@
+#include <shell>
+
+enum struct MyStruct
+{
+    int v;
+    float f;
+    char sz[8];
+}
+
+MyStruct CreateStruct()
+{
+    MyStruct st;
+    st.v = 1;
+    st.f = 1.0;
+    st.sz = "Hello";
+    return st;
+}
+
+void PrintStruct(MyStruct st)
+{
+    printnums(st.v);
+    printfloat(st.f);
+    print(st.sz);
+    print("\n");
+}
+
+public void main() 
+{
+    print("First Struct\n");
+    MyStruct st;
+    st = CreateStruct();
+    PrintStruct(st);
+    st = CreateStruct();
+    PrintStruct(st);
+    st = CreateStruct();
+    PrintStruct(st);
+    print("New Struct Below\n");
+    MyStruct st2;
+    st2 = CreateStruct();
+    PrintStruct(st2);
+    st2 = CreateStruct();
+    PrintStruct(st2);
+    st2 = CreateStruct();
+    PrintStruct(st2);
+}