sbc8641d: Fix PCI mapping concepts

Rename _BASE to _BUS, as it's actually a PCI bus address,
separate virtual and physical addresses into _VIRT and _PHYS,
and use each appopriately.  This makes the code easier to read
and understand, and facilitates mapping changes going forward.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
diff --git a/board/sbc8641d/sbc8641d.c b/board/sbc8641d/sbc8641d.c
index 1471e58..508bdc5 100644
--- a/board/sbc8641d/sbc8641d.c
+++ b/board/sbc8641d/sbc8641d.c
@@ -247,14 +247,14 @@
 
 		/* outbound memory */
 		pci_set_region(r++,
-			       CONFIG_SYS_PCI1_MEM_BASE,
+			       CONFIG_SYS_PCI1_MEM_BUS,
 			       CONFIG_SYS_PCI1_MEM_PHYS,
 			       CONFIG_SYS_PCI1_MEM_SIZE,
 			       PCI_REGION_MEM);
 
 		/* outbound io */
 		pci_set_region(r++,
-			       CONFIG_SYS_PCI1_IO_BASE,
+			       CONFIG_SYS_PCI1_IO_BUS,
 			       CONFIG_SYS_PCI1_IO_PHYS,
 			       CONFIG_SYS_PCI1_IO_SIZE,
 			       PCI_REGION_IO);
@@ -290,14 +290,14 @@
 
 	/* outbound memory */
 	pci_set_region(r++,
-		       CONFIG_SYS_PCI2_MEM_BASE,
+		       CONFIG_SYS_PCI2_MEM_BUS,
 		       CONFIG_SYS_PCI2_MEM_PHYS,
 		       CONFIG_SYS_PCI2_MEM_SIZE,
 		       PCI_REGION_MEM);
 
 	/* outbound io */
 	pci_set_region(r++,
-		       CONFIG_SYS_PCI2_IO_BASE,
+		       CONFIG_SYS_PCI2_IO_BUS,
 		       CONFIG_SYS_PCI2_IO_PHYS,
 		       CONFIG_SYS_PCI2_IO_SIZE,
 		       PCI_REGION_IO);