[FIX] partner_firstname - adapt partner form inherit to new partner form

partner_firstname/partner_view.xml

@@ -26,7 +26,7 @@
           </group>
         </field>
         <!-- Add firstname last name in contact for also -->
-        <xpath expr="//page[@string='Contacts']/field/form/div/group/field[@name='name']" position="after">
+        <xpath expr="//form[@string='Contact']/sheet/div/h1/field[@name='name']" position="after">
             <field name="lastname"/>
             <field name="firstname"/>
         </xpath>