[S390] cio: avoid memory leak on error in css_alloc_subchannel().

sch->lock has been allocated in cio_validate_subchannel(), it must be
freed if cio_modify() fails.
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/css.c

@@ -79,6 +79,7 @@ css_alloc_subchannel(struct subchannel_id schid)
 	sch->schib.pmcw.intparm = (__u32)(unsigned long)sch;
 	ret = cio_modify(sch);
 	if (ret) {
+		kfree(sch->lock);
 		kfree(sch);
 		return ERR_PTR(ret);
 	}