wifi: ath12k: fix read pointer after free in ath12k_mac_assign_vif_to_vdev()

wifi: ath12k: fix read pointer after free in ath12k_mac_assign_vif_to_vdev()

In ath12k_mac_assign_vif_to_vdev(), if arvif is created on a different
radio, it gets deleted from that radio through a call to
ath12k_mac_unassign_link_vif(). This action frees the arvif pointer.
Subsequently, there is a check involving arvif, which will result in a
read-after-free scenario.

Fix this by moving this check after arvif is again assigned via call to
ath12k_mac_assign_link_vif().

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1

Closes: https://scan5.scan.coverity.com/#/project-view/63541/10063?selectedIssue=1636423
Fixes: b5068bc9180d ("wifi: ath12k: Cache vdev configs before vdev create")
Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Acked-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Acked-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/20241210-read_after_free-v1-1-969f69c7d66c@quicinc.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>