wifi: ath11k: avoid forward declaration of ath11k_mac_start_vdev_delay()

Currently ath11k_mac_start_vdev_delay() needs a forward declaration because
it is defined after where it is called. Avoid this by re-arranging
ath11k_mac_station_add() and ath11k_mac_op_sta_state().

No functional changes. Compile tested only.

Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20240123025700.2929-4-quic_bqiang@quicinc.com