wifi: ath11k: fix a possible dead lock caused by ab->base_lock

spin_lock()/spin_unlock() are used in ath11k_reg_chan_list_event() to
acquire/release ab->base_lock. For now this is safe because that
function is only called in soft IRQ context.

But ath11k_reg_chan_list_event() will be called from process
context in an upcoming patch, and this can result in a deadlock if
ab->base_lock is acquired in process context and then soft IRQ occurs
on the same CPU and tries to acquire that lock.

Fix it by using spin_lock_bh() and spin_unlock_bh() instead.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23

Fixes: 69a0fcf8 ("ath11k: Avoid reg rules update during firmware recovery")
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Signed-off-by: Wen Gong <quic_wgong@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20231218085844.2658-4-quic_bqiang@quicinc.com