Wrong C code generation for sequence types

When generating the C code with

$AXIS2C_HOME/bin/tools/wsdl2c/WSDL2C.sh -uri $WSDL_PATH -ss -sd -d adb -u -o $SKEL_OUT_PATH

For an element like:

    <xsd:complexType name="MyType">
        <xsd:sequence>
            <xsd:element name="MyName" type="MyElementType" minOccurs="0" maxOccurs="unbounded"/>
        </xsd:sequence>
    </xsd:complexType>

(notice the `maxOccurs="unbounded"`)

The type of "MyElementType" is incorrectly set to the parent "MyType" element and hence the generated message is wrong.

To workaround the issue it's necessary to comment out the following line in the generated type "adb_MyElementType.c", function  "adb_MyElementType_serialize_obj":

axiom_element_add_attribute (parent_element, env, xsi_type_attri, parent);

reported by rbarriuso

Original submission: https://issues.apache.org/jira/browse/AXIS2-5958