Three reasons:
1. this flag doesn't work for ppc64 (see commit dc7b08b);
2. clang is not aware of this flag;
3. all seems to work just fine without it.

Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>