Minor changes:

Minor changes:
- Use FBSDID.
- Remove unused macro.
- Use auto-generated typedefs for the prototypes of the bus and device
  interface functions.
- Terminate the output of device_printf(9) with a newline char.
- Honour the return values of malloc(), OF_getprop(), etc.
- Use __func__ instead of hardcoded function names.
- Print the physical slot number and the board model on attach.

MFC after:	1 month