wifi: ath12k: refactor PCI window register access

wifi: ath12k: refactor PCI window register access

Currently offset of PCI window register address is defined as 0x310c which
is same across existing chips. However QCC2072 has a different offset
0x3278.

In order to make the window selection logic work for QCC2072 as well,
change to initialize this parameter per device at the probe time.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3

Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20260112-ath12k-support-qcc2072-v2-1-fc8ce1e43969@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>