s390/pci: Rework MSI descriptor walk

Replace the about to vanish iterators and make use of the filtering.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20211206210748.305656158@linutronix.de

arch/s390/pci/pci_irq.c

@@ -303,7 +303,7 @@ int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 
 	/* Request MSI interrupts */
 	hwirq = bit;
-	for_each_pci_msi_entry(msi, pdev) {
+	msi_for_each_desc(msi, &pdev->dev, MSI_DESC_NOTASSOCIATED) {
 		rc = -EIO;
 		if (hwirq - bit >= msi_vecs)
 			break;
@@ -362,9 +362,7 @@ void arch_teardown_msi_irqs(struct pci_dev *pdev)
 		return;
 
 	/* Release MSI interrupts */
-	for_each_pci_msi_entry(msi, pdev) {
-		if (!msi->irq)
-			continue;
+	msi_for_each_desc(msi, &pdev->dev, MSI_DESC_ASSOCIATED) {
 		irq_set_msi_desc(msi->irq, NULL);
 		irq_free_desc(msi->irq);
 		msi->msg.address_lo = 0;