fsl_pci: Only modify registers if we have them

pme_msg_det exists only on PCIe controllers only set it if we are a "bridge".

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/drivers/pci/fsl_pci_init.c b/drivers/pci/fsl_pci_init.c
index 68e45e1..7dc33be 100644
--- a/drivers/pci/fsl_pci_init.c
+++ b/drivers/pci/fsl_pci_init.c
@@ -182,7 +182,8 @@
 
 	/* Clear all error indications */
 
-	pci->pme_msg_det = 0xffffffff;
+	if (bridge)
+		pci->pme_msg_det = 0xffffffff;
 	pci->pedr = 0xffffffff;
 
 	pci_hose_read_config_word (hose, dev, PCI_DSR, &temp16);