ath10k: do not warn about unsupported vdev param

10.X firmware does not support WMI_VDEV_PARAM_TX_ENCAP_TYPE.
It's a known limitation and we should not warn about this.

Signed-off-by: Bartosz Markowski <bartosz.markowski@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>