powerpc/pci: Fix IMMRBAR address

For PEXCSRBAR, bit 3-0 indicate prefetchable and address type.
So when getting base address, these bits should be masked,
otherwise we may get incorrect base address.
Signed-off-by: NMinghuan Lian <Minghuan.Lian@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

arch/powerpc/sysdev/fsl_pci.c

@@ -868,6 +868,14 @@ u64 fsl_pci_immrbar_base(struct pci_controller *hose)
 
 		pci_bus_read_config_dword(hose->bus,
 			PCI_DEVFN(0, 0), PCI_BASE_ADDRESS_0, &base);
+
+		/*
+		 * For PEXCSRBAR, bit 3-0 indicate prefetchable and
+		 * address type. So when getting base address, these
+		 * bits should be masked
+		 */
+		base &= PCI_BASE_ADDRESS_MEM_MASK;
+
 		return base;
 	}
 #endif