[POWERPC] ibmebus: More descriptive error return code in ibmebus_store_probe()

Signed-off-by: NJoachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/kernel/ibmebus.c

@@ -400,7 +400,7 @@ static ssize_t ibmebus_store_probe(struct bus_type *bus,
 			    ibmebus_match_path)) {
 		printk(KERN_WARNING "%s: %s has already been probed\n",
 		       __FUNCTION__, path);
-		rc = -EINVAL;
+		rc = -EEXIST;
 		goto out;
 	}