ipr: Clear interrupt on croc/crocodile when running with LSI

If we fall back to using LSI on the Croc or Crocodile chip we need to
clear the interrupt so we don't hang the system.

Cc: <stable@vger.kernel.org>
Tested-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ipr.c

@@ -10093,6 +10093,7 @@ static int ipr_probe_ioa(struct pci_dev *pdev,
 		ioa_cfg->intr_flag = IPR_USE_MSI;
 	else {
 		ioa_cfg->intr_flag = IPR_USE_LSI;
+		ioa_cfg->clear_isr = 1;
 		ioa_cfg->nvectors = 1;
 		dev_info(&pdev->dev, "Cannot enable MSI.\n");
 	}