[coreboot] KGPE-D16 AMD-vi fails because combined sata is enabled

[Taiidan at gmx.com]

Hmm it works for me on Xen 4.10 (I don't normally use xen but I 
installed it to check for you)

(XEN) AMD-Vi: Disabled HAP memory map sharing with IOMMU
(XEN) AMD-Vi: IOMMU 0 Enabled.
(XEN) I/O virtualisation enabled
(XEN)  - Dom0 mode: Strict
(XEN) Interrupt remapping enabled

Btw does anyone know what the difference is between strict and relaxed 
dom0 mode?