wifi: ath12k: introduce QMI firmware ready flag

When hardware device group abstraction is introduced, the QMI firmware ready
event of different devices in a group can be received simultaneously. To
indicate the firmware ready event is completed for a particular device in a
group set a flag (ATH12K_FLAG_QMI_FW_READY_COMPLETE). This helps the upcoming
hardware recovery implementation for hardware device group abstraction.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Signed-off-by: Karthikeyan Periyasamy <quic_periyasa@quicinc.com>
Signed-off-by: Harshitha Prem <quic_hprem@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Patchwork-Id: 13888259