AHCI: Make distinct names for ports in /proc/interrupts

Currently all interrupts assigned to AHCI ports show up in
'/proc/interrupts' as 'ahci'. This fix adds port numbers as
suffixes and hence makes the descriptions distinct.

Reported-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 251e57d3..4d1c672 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1142,9 +1142,11 @@
 		return rc;
 
 	for (i = 0; i < host->n_ports; i++) {
+		struct ahci_port_priv *pp = host->ports[i]->private_data;
+
 		rc = devm_request_threaded_irq(host->dev,
 			irq + i, ahci_hw_interrupt, ahci_thread_fn, IRQF_SHARED,
-			dev_driver_string(host->dev), host->ports[i]);
+			pp->irq_desc, host->ports[i]);
 		if (rc)
 			goto out_free_irqs;
 	}