i2c-ali1563: Fix device initialization

The i2c-ali1563 initialization looks quite broken to me:
* If the I/O space isn't enabled, we forcibly set 3 bits in
  the PCI configuration space instead of just the one enabling
  the I/O space.
* After that we pretend to check if the write worked, but we
  don't actually read the new value from the register.
* It's probably not a good idea to enable the I/O space if no
  base address has been set.

So I propose the following changes to that part of the driver:
* Merge ali1563_enable() into ali1563_setup().
* Check the base address before the I/O space enabled bit.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Rudolf Marek <r.marek@assembler.cz>