wifi: ath12k: Support channel change stats

wifi: ath12k: Support channel change stats

Add support to request channel change stats from the firmware through
HTT stats type 76. These stats give channel switch details like the
channel that the radio changed to, its center frequency, time taken
for the switch, chainmask details, etc.

Sample output:
echo 76 > /sys/kernel/debug/ath12k/pci-0000\:06\:00.0/mac0/htt_stats_type
cat /sys/kernel/debug/ath12k/pci-0000\:06\:00.0/mac0/htt_stats
Channel Change Timings:
|PRIMARY CHANNEL FREQ|BANDWIDTH CENTER FREQ|PHYMODE|TX_CHAINMASK|RX_CHAINMASK|SWITCH TIME(us)|INI(us)|TPC+CTL(us)|CAL(us)|MISC(us)|CTL(us)|SW PROFILE|
|                5200|                 5200|     24|          15|          15|         448850|   2410|      10546| 434593|    1071|   1100|         4|
|                5240|                 5240|     24|          15|          15|         450730|   4106|      10524| 434528|    1306|   1150|         4|
|                5180|                 5210|     26|          15|          15|         467894|   4764|      10438| 451101|    1337|   1508|         4|
|                5200|                 5200|      0|          15|          15|          13838|   2692|       1736|   8558|     686|    802|         6|
|                5180|                 5180|      0|          15|          15|          13465|   3207|        855|   8579|     578|    760|         6|
|                5200|                 5200|     24|          15|          15|         570321|   2441|      10439| 555661|    1574|    949|         4|

Note: QCC2072 and WCN7850 firmware does not support HTT stats type 76.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.6-01181-QCAHKSWPL_SILICONZ-1

Signed-off-by: Harish Rachakonda <quic_rachakon@quicinc.com>
Signed-off-by: Roopni Devanathan <roopni.devanathan@oss.qualcomm.com>
Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Link: https://patch.msgid.link/20260326050641.3066562-1-roopni.devanathan@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>