qeth: Clear SBALF15 in any case for output buffers.

Function qeth_clear_output_buffer for HiperSockets may not clear
all 16 SBALEs, but only the used ones. The error flag in SBALF15
has to be cleared in any case.
Signed-off-by: NKlaus-Dieter Wacker <kdwacker@de.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/s390/net/qeth_core_main.c

@@ -952,6 +952,7 @@ static void qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
 		buf->buffer->element[i].addr = NULL;
 		buf->buffer->element[i].flags = 0;
 	}
+	buf->buffer->element[15].flags = 0;
 	buf->next_element_to_fill = 0;
 	atomic_set(&buf->state, QETH_QDIO_BUF_EMPTY);
 }