pci: fix checking PCI_REGION_MEM in pci_hose_phys_to_bus()

When converting between PCI bus and phys addresses, a two pass search
was introduced with preference to non-PCI_REGION_SYS_MEMORY regions.
See commit 2d43e873a29ca4959ba6a30fc7fb396d3fd0dccf.

However, since PCI_REGION_MEM is defined as 0, the if statement was
always asserted true: ((flags & PCI_REGION_MEM) == PCI_REGION_MEM)

This patch uses PCI_REGION_TYPE bit to check if the region is
PCI_REGION_MEM: ((flags & PCI_REGION_TYPE) == PCI_REGION_MEM)

Signed-off-by: Cheng Gu <chenggu@marvell.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/pci/pci_common.c b/drivers/pci/pci_common.c
index 07f1726..a64792f 100644
--- a/drivers/pci/pci_common.c
+++ b/drivers/pci/pci_common.c
@@ -231,7 +231,7 @@
 	 * if PCI_REGION_MEM is set we do a two pass search with preference
 	 * on matches that don't have PCI_REGION_SYS_MEMORY set
 	 */
-	if ((flags & PCI_REGION_MEM) == PCI_REGION_MEM) {
+	if ((flags & PCI_REGION_TYPE) == PCI_REGION_MEM) {
 		ret = __pci_hose_bus_to_phys(hose, bus_addr,
 				flags, PCI_REGION_SYS_MEMORY, &phys_addr);
 		if (!ret)
@@ -298,7 +298,7 @@
 	 * if PCI_REGION_MEM is set we do a two pass search with preference
 	 * on matches that don't have PCI_REGION_SYS_MEMORY set
 	 */
-	if ((flags & PCI_REGION_MEM) == PCI_REGION_MEM) {
+	if ((flags & PCI_REGION_TYPE) == PCI_REGION_MEM) {
 		ret = __pci_hose_phys_to_bus(hose, phys_addr,
 				flags, PCI_REGION_SYS_MEMORY, &bus_addr);
 		if (!ret)