Time synchronization was not properly enabled on non-MSI-X platforms.

Fixes: 2c344ae2 ("igc: Add support for TX timestamping")
Signed-off-by: NJames McLaughlin <james.mclaughlin@qsc.com>
Reviewed-by: NVinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: NNechama Kraus <nechamax.kraus@linux.intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>