ath11k: fix missing unlock on error in ath11k_wow_op_resume()

Add the missing unlock before return from function ath11k_wow_op_resume()
in the error handling case.

Fixes: 90bf5c8d ("ath11k: purge rx pktlog when entering WoW")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220408030912.3087293-1-yangyingliang@huawei.com