More then 1 Piface (address rule)

Feature Requests
1

Is it possible to make an address rule to select the address of the Piface.
It’s now impossible to get more then one Piface.
I see that HA used digitalio for control the Piface and the rule in digitalio is:

   p.digital_write(port,value,board_address)

In HA it says:

def write_output(port, value):
    """Write a value to a PFIO."""
    PFIO.digital_write(port, value)

I think it’s possible to make an address rule, but I’m no programmer.
Example:

```
 # Example configuration.yaml entry
switch:
  - platform: rpi_pfio
     board_address: 1      #address for Piface
     ports:
       0:
         name: Doorlock
         invert_logic: true
       1:
         name: Light Desk