sconfig: rename pci_domain -> domain

The name pci_domain was a bit misleading, since the construct is only
PCI specific in a particular (northbridge/cpu) implementation, but not
by concept. As implementations and hardware change, be more generic
about our naming. This will allow us to support non-PCI systems without
adding new keywords.

Change-Id: Ide885a1d5e15d37560c79b936a39252150560e85
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/2376
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/mainboard/ibm/e325/devicetree.cb

@@ -4,7 +4,7 @@ chip northbridge/amd/amdk8/root_complex
 			device lapic 0 on end
 		end
 	end
-	device pci_domain 0 on
+	device domain 0 on
 		chip northbridge/amd/amdk8
 			device pci 18.0 on end # LDT 0
 			device pci 18.0 on     # LDT 1

src/mainboard/ibm/e326/devicetree.cb

@@ -5,7 +5,7 @@ chip northbridge/amd/amdk8/root_complex
 		end
 	end
 
-	device pci_domain 0 on
+	device domain 0 on
 		chip northbridge/amd/amdk8
 			device pci 18.0 on end # LDT 0
 			device pci 18.0 on     # LDT 1