[coreboot] SATA init on FSP 2.0 for Skylake

[roman perepelitsin]

Hi!
I got a little problem with SATA controller in H110 Skylake PCH (desktop).
SATA device geographical address - 0:17h:0 on PCI, and it enabled via
devicetree.cb. This params correctly send in FspSiliconInit. After this
coreboot run PCI bus scan. And my SATA device return 0xffffffff on PCI read
config cycles. I search in Intel datasheet for specific SATA disable pin or
something else, but there is no methods that can make SATA inactive. Maybe
somebody advice about it?