wifi: ath10k: Fix memory leak on unsupported WMI command

wifi: ath10k: Fix memory leak on unsupported WMI command

ath10k_wmi_cmd_send takes ownership of the passed buffer (skb) and has the
responsibility to release it in case of error. This patch fixes missing
free in case of early error due to unhandled WMI command ID.

Tested-on: WCN3990 hw1.0 WLAN.HL.3.3.7.c2-00931-QCAHLSWMTPLZ-1

Fixes: 553215592f14 ("ath10k: warn if give WMI command is not supported")
Suggested-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Link: https://patch.msgid.link/20250926195656.187970-1-loic.poulain@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>