disabling oplocks/leases via module parm enable_oplocks broken for SMB3

leases (oplocks) were always requested for SMB2/SMB3 even when oplocks
disabled in the cifs.ko module.

Signed-off-by: Steve French <steve.french@primarydata.com>
Reviewed-by: Chandrika Srinivasan <chandrika.srinivasan@citrix.com>
CC: Stable <stable@vger.kernel.org>