I/OAT: do not set DCACTRL_CMPL_WRITE_ENABLE for I/OAT ver.3

Flag DCACTRL_CMPL_WRITE_ENABLE is valid only for I/OAT ver.2
so it should not be set for I/OAT ver.3.

Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>