[FIX] mrp: display info text on work orders view

When seeing the work orders view, it would display an empty black box instead of
the proper message.

The message is not displaed since creation is deactivated.

opw 1839001

addons/mrp/views/mrp_workorder_views.xml

@@ -404,6 +404,8 @@
         <field name="context">{'search_default_ready': True, 'search_default_progress': True}</field>
         <field name="help" type="html">
           <p class="oe_view_nocontent_create">
+            Click to start a new work order.
+          </p><p>
             Work Orders are operations to be processed at a Work Center to realize a
             Manufacturing Order. Work Orders are trigerred by Manufacturing Orders,
             they are based on the Routing defined on these ones.