i2c: pasemi: remove hardcoded bus numbers on smbus

The pasemi smbus controller uses PCI_FUNC(dev->devfn) to define which
number bus to attach to, however this fails when something else is
probed first, for example an ATI Radeon graphics card will claim 9 or
10 busses, including the ones the pasemi wants.
Patch the driver to call i2c_add_adapter rather than
i2c_add_numbered_adapter.

Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>