PCI: Disable AER with pci=nomsi

When booting with pci=nomsi aer causes lost interrupts and
lockdep inversions.

So check if MSIs are not disabled before initializing the aer
driver.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/pcie/aer/aerdrv.c

@@ -318,6 +318,8 @@ static int __init aer_service_init(void)
 {
 	if (pcie_aer_disable)
 		return -ENXIO;
+	if (!pci_msi_enabled())
+		return -ENXIO;
 	return pcie_port_service_register(&aerdriver);
 }