Fix #7019, Pad host field in notes -d command

The notes -d command is always expecting a host address, but
fileformat exploits don't have this type of information when the
exploit file is generated, therefore there isn't enough fields
provided for Rex table.

Fix #7019

lib/msf/ui/console/command_dispatcher/db.rb

@@ -1360,6 +1360,8 @@ class Db
           addr = (host.scope ? host.address + '%' + host.scope : host.address )
           rhosts << addr
         end
+      else
+        csv_note << ''
       end
       if (note.service)
         msg << " service=#{note.service.name}" if note.service.name