wifi: ath11k: fix refcount leak in ath11k_ahb_fw_resources_init()

wifi: ath11k: fix refcount leak in ath11k_ahb_fw_resources_init()

of_get_child_by_name() returns a node pointer with refcount
incremented, but the error path when ath11k_ahb_setup_msa_resources()
fails does not release it.  Add the missing of_node_put() to avoid
leaking the reference.

Cc: stable@vger.kernel.org
Fixes: 095cb947490c ("wifi: ath11k: allow missing memory-regions")
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>
Link: https://patch.msgid.link/20260609092528.220547-1-vulab@iscas.ac.cn
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>