pci: Rename PCI_REGION_MEMORY to PCI_REGION_SYS_MEMORY for clarity

The PCI_REGION_MEMORY and PCI_REGION_MEM are a bit to similar and
can be confusing when reading the code.

Rename PCI_REGION_MEMORY to PCI_REGION_SYS_MEMORY to clarify its used
for system memory mapping purposes.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/board/tb0229/vr4131-pci.c b/board/tb0229/vr4131-pci.c
index 4c91923..6ff4293 100644
--- a/board/tb0229/vr4131-pci.c
+++ b/board/tb0229/vr4131-pci.c
@@ -235,7 +235,7 @@
 	pci_set_region (hose->regions + 3,
 			0x00000000,
 			0x80000000,
-			0x04000000, PCI_REGION_MEM | PCI_REGION_MEMORY);
+			0x04000000, PCI_REGION_MEM | PCI_REGION_SYS_MEMORY);
 
 	hose->region_count = 4;