hwmon: (k10temp) Use API function to access System Management Network

hwmon: (k10temp) Use API function to access System Management Network

The SMN (System Management Network) on Family 17h AMD CPUs is also accessed
from other drivers, specifically EDAC. Accessing it directly is racy.
On top of that, accessing the SMN through root bridge 00:00 is wrong on
multi-die CPUs and may result in reading the temperature from the wrong
die. Use available API functions to fix the problem.

For this to work, add dependency on AMD_NB. Also change the Raven Ridge
PCI device ID to point to Data Fabric Function 3, since this ID is used
by the API functions to find the CPU node.

Cc: stable@vger.kernel.org # v4.16+
Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>