wifi: ath11k: fix memory leaks in beacon template setup

wifi: ath11k: fix memory leaks in beacon template setup

The functions ath11k_mac_setup_bcn_tmpl_ema() and
ath11k_mac_setup_bcn_tmpl_mbssid() allocate memory for beacon templates
but fail to free it when parameter setup returns an error.

Since beacon templates must be released during normal execution, they
must also be released in the error handling paths to prevent memory
leaks.

Fix this by using unified exit paths with proper cleanup in the respective
error paths.

Compile tested only. Issue found using a prototype static analysis tool
and code review.

Fixes: 3a415daa3e8b ("wifi: ath11k: add P2P IE in beacon template")
Fixes: 335a92765d30 ("wifi: ath11k: MBSSID beacon support")
Suggested-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Link: https://patch.msgid.link/20260130084451.110768-1-zilin@seu.edu.cn
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>