item: fix a conflict in field libraries

erp5_trade contains Base_viewTradeFieldLibrary which contain
my_dialog_mode_portal_type, which is a multi list field where user can
select multiple lines portal types. It is used in
DeliveryModule_viewDeliveryLineReportDialog/your_portal_type

erp5_item also contains Base_viewTradeFieldLibrary , for cases where
erp5_item extend trade module to select items. It also contains a
my_dialog_mode_portal_type field, where user can select item portal type.
That field is not a multi-list field, but a list-field. It is used in
DeliveryLine_viewSelectItemListDialog

So when erp5_item is installed, it overrides
Base_viewTradeFieldLibrary/my_dialog_mode_portal_type with a list field
instead of a multi-list field and breaks
DeliveryModule_viewDeliveryLineReportDialog, because user can no longer
select more than one portal type.

This renames the field in erp5_item, now we have:
 * Base_viewTradeFieldLibrary/my_dialog_mode_portal_type for movement
portal types
 * Base_viewTradeFieldLibrary/my_dialog_mode_item_portal_type for item
portal type

bt5/erp5_item/SkinTemplateItem/portal_skins/erp5_item_trade/Base_viewTradeFieldLibrary.xml

@@ -101,7 +101,7 @@
                         <string>my_dialog_mode_total_quantity</string>
                         <string>my_dialog_mode_type</string>
                         <string>my_dialog_mode_quantity_unit</string>
-                        <string>my_dialog_mode_portal_type</string>
+                        <string>my_dialog_mode_item_portal_type</string>
                         <string>my_dialog_mode_reference</string>
                         <string>my_dialog_mode_title</string>
                         <string>my_dialog_mode_delivery_line_quantity_unit</string>

bt5/erp5_item/SkinTemplateItem/portal_skins/erp5_item_trade/Base_viewTradeFieldLibrary/my_dialog_mode_portal_type.xml → bt5/erp5_item/SkinTemplateItem/portal_skins/erp5_item_trade/Base_viewTradeFieldLibrary/my_dialog_mode_item_portal_type.xml

@@ -17,7 +17,7 @@
         </item>
         <item>
             <key> <string>id</string> </key>
-            <value> <string>my_dialog_mode_portal_type</string> </value>
+            <value> <string>my_dialog_mode_item_portal_type</string> </value>
         </item>
         <item>
             <key> <string>message_values</string> </key>

bt5/erp5_item/SkinTemplateItem/portal_skins/erp5_item_trade/DeliveryLine_viewSelectItemListDialog/your_portal_type.xml

@@ -71,7 +71,7 @@
               <dictionary>
                 <item>
                     <key> <string>field_id</string> </key>
-                    <value> <string>my_dialog_mode_portal_type</string> </value>
+                    <value> <string>my_dialog_mode_item_portal_type</string> </value>
                 </item>
                 <item>
                     <key> <string>form_id</string> </key>