[FIX] mrp: Missing log in procurement chatter when cancelling a MO.

When a MO is cancelled, it sets the related procurements in exception.
This fix logs this action in the procurement chatter, for WMS administration
and maintenance purposes.

addons/mrp/mrp.py

@@ -772,6 +772,7 @@ class mrp_production(osv.osv):
         proc_obj = self.pool.get("procurement.order")
         procs = proc_obj.search(cr, uid, [('production_id', 'in', ids)], context=context)
         if procs:
+            proc_obj.message_post(cr, uid, procs, body=_('Manufacturing order cancelled.'), context=context)
             proc_obj.write(cr, uid, procs, {'state': 'exception'}, context=context)
         return True