wifi: ath12k: add hw_link_id in ath12k_pdev

Currently, hw_link_id is sent in WMI service ready event but it
is not parsed anywhere.

But, in future, for multi-link operation, this parameter would be
needed by many WMI commands such as WMI beacon template
(WMI_BCN_TMPL_CMDID), WMI vdev start for Multi-link virtual AP
interfaces (WMI_VDEV_START_REQUEST_CMDID), WMI peer assoc command
(WMI_PEER_ASSOC_CMDID) for Multi-link peer and so on.

Hence, add changes to parse and store the hw_link_id received in
WMI service ready event in ath12k_pdev structure.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0.1-00029-QCAHKSWPL_SILICONZ-1

Signed-off-by: Karthikeyan Periyasamy <quic_periyasa@quicinc.com>
Signed-off-by: Harshitha Prem <quic_hprem@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20240529054955.4105240-1-quic_hprem@quicinc.com