ide: print message on error in ide_find_port_slot()

* Add DRV_NAME define to ide-h8300.c.

* Fix ide-h8300.c, swarm.c and sgiioc4.c to set .name field in
  struct ide_port_info to DRV_NAME, then convert these host drivers
  to use ide_find_port_slot() instead of ide_find_port().

* Print message on error in ide_find_port_slot().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
index c5dc188..235ebdb 100644
--- a/drivers/ide/ide-probe.c
+++ b/drivers/ide/ide-probe.c
@@ -1490,6 +1490,9 @@
 		}
 	}
 
+	printk(KERN_ERR "%s: no free slot for interface\n",
+			d ? d->name : "ide");
+
 	return NULL;
 
 out_found: