abituguru3: prefer DMI probing to manual probing

Previously the driver was only using DMI to prevent smbus probing on
non-Abit motherboards.  However, since the manual probing method is
brittle and prone to failure on some Abit motherboards (esp.  the Abit
IP35 Pro) it is better to use DMI to also read the board name and then
decide whether or not to probe the bus.

At the moment, we do not have a list of valid DMI name strings to use
for existing and supported motherboards.  This patch only implements DMI
probing for the IP35 Pro.  For motherboards that can not yet use DMI
probing, a warning will be printed to the kernel log asking those users
to email me their dmidecode output.

The existing manual probing mechanism will be used if CONFIG_DMI is not
enabled, if DMI probing fails (for DMI-unsupported motherboards), or if
DMI probing fails and the "force" option is set (for DMI-supported
motherboards).  Ideally in the longer term this manual probing method
would be removed.

This patch should be safe to apply as it does not change the probing
behaviour for most of the supported motherboards, just the IP35 Pro,
which already has regressions filed against it in 2.6.26.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=11212

Signed-off-by: Alistair John Strachan <alistair@devzero.co.uk>
Acked-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>