AMD Bald Eagle: Add northbridge files for new AMD processor

Also fix a typo in a config option for SteppeEagle.

Change-Id: Iad51cc917217aa0eac751dc805c304652d20e066
Signed-off-by: Bruce Griffith <Bruce.Griffith@se-eng.com>
Signed-off-by: Dave Frodin <dave.frodin@se-eng.com>
Reviewed-on: http://review.coreboot.org/7247
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc.jones@se-eng.com>
15 files changed