MSI: Consolidate precondition checks

Consolidate precondition checks into a single if statement.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index d5b9b94..b6dc69e 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -525,12 +525,7 @@
 	struct msi_desc *entry;
 	int default_irq;
 
-	if (!pci_msi_enable)
-		return;
-	if (!dev)
-		return;
-
-	if (!dev->msi_enabled)
+	if (!pci_msi_enable || !dev || !dev->msi_enabled)
 		return;
 
 	msi_set_enable(dev, 0);
@@ -656,12 +651,7 @@
 
 void pci_disable_msix(struct pci_dev* dev)
 {
-	if (!pci_msi_enable)
-		return;
-	if (!dev)
-		return;
-
-	if (!dev->msix_enabled)
+	if (!pci_msi_enable || !dev || !dev->msix_enabled)
 		return;
 
 	msix_set_enable(dev, 0);