ath11k: add separate APIs for monitor mode

Add separate APIs for monitor_vdev_create/monitor_vdev_delete
and monitor_vdev_start/monitor_vdev_stop.

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-01725-QCAHKSWPL_SILICONZ-1

Co-developed-by: Miles Hu <milehu@codeaurora.org>
Signed-off-by: Miles Hu <milehu@codeaurora.org>
Co-developed-by: Vasanthakumar Thiagarajan <vthiagar@codeaurora.org>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@codeaurora.org>
Signed-off-by: Seevalamuthu Mariappan <seevalam@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210721162053.46290-3-jouni@codeaurora.org