wifi: ath10k: Fix connection after GTK rekeying

wifi: ath10k: Fix connection after GTK rekeying

It appears that not all hardware/firmware implementations support
group key deletion correctly, which can lead to connection hangs
and deauthentication following GTK rekeying (delete and install).

To avoid this issue, instead of attempting to delete the key using
the special WMI_CIPHER_NONE value, we now replace the key with an
invalid (random) value.

This behavior has been observed with WCN39xx chipsets.

Tested-on: WCN3990 hw1.0 WLAN.HL.3.3.7.c2-00931-QCAHLSWMTPLZ-1
Reported-by: Alexey Klimov <alexey.klimov@linaro.org>
Closes: https://lore.kernel.org/all/DAWJQ2NIKY28.1XOG35E4A682G@linaro.org
Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Tested-by: Alexey Klimov <alexey.klimov@linaro.org> # QRB2210 RB1
Link: https://patch.msgid.link/20250902143225.837487-1-loic.poulain@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>