pci: Indicate prefetchable memory allocate when debugging

At present the PCI output displays 'Mem' when it allocates memory for a PCI
device, whether it is prefetchable or not. There is a distinction since the
memory comes from separate pools. Use 'Prf' instead of 'Mem' when allocating
prefetchable memory.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/pci/pci_auto.c b/drivers/pci/pci_auto.c
index 51d2ac0..41d5447 100644
--- a/drivers/pci/pci_auto.c
+++ b/drivers/pci/pci_auto.c
@@ -148,8 +148,9 @@
 				bar_res = mem;
 #endif
 
-			debug("PCI Autoconfig: BAR %d, Mem, size=0x%llx, ",
-			      bar_nr, (unsigned long long)bar_size);
+			debug("PCI Autoconfig: BAR %d, %s, size=0x%llx, ",
+			      bar_nr, bar_res == prefetch ? "Prf" : "Mem",
+			      (unsigned long long)bar_size);
 		}
 
 #ifndef CONFIG_PCI_ENUM_ONLY