wifi: ath11k: Really consistently use ath11k_vif_to_arvif()

Commit 9476cda4 ("wifi: ath11k: Consistently use ath11k_vif_to_arvif()")
previously replaced all open coding of the ath11k_vif_to_arvif()
functionality. Subsequently two more instances of open coding were
introduced, one in commit 92425f78 ("wifi: ath11k: fill parameters for
vdev set tpc power WMI command") and one in commit 6f4e235b

 ("wifi:
ath11k: add parse of transmit power envelope element"), so fix those as
well.

No functional changes, compile tested only.

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20240205-ath11k_vif_to_arvif-v1-1-7c41313c8318@quicinc.com