wifi: ath12k: fix atomic calls in ath12k_mac_op_set_bitrate_mask()

In the Linux kernel, the following vulnerability has been resolved:

wifi: ath12k: fix atomic calls in ath12k_mac_op_set_bitrate_mask()

When I try to manually set bitrates:

iw wlan0 set bitrates legacy-2.4 1

I get sleeping from invalid context error, see below. Fix that by switching to
use recently introduced ieee80211_iterate_stations_mtx().

Do note that WCN6855 firmware is still crashing, I'm not sure if that firmware
even supports bitrate WMI commands and should we consider disabling
ath12k_mac_op_set_bitrate_mask() for WCN6855? But that's for another patch.

BUG: sleeping function called from invalid context at drivers/net/wireless/ath/ath12k/wmi.c:420
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 2236, name: iw
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
3 locks held by iw/2236:
#0: ffffffffabc6f1d8 (cb_lock){++++}-{3:3}, at: genl_rcv+0x14/0x40
#1: ffff888138410810 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: nl80211_pre_doit+0x54d/0x800 [cfg80211]
#2: ffffffffab2cfaa0 (rcu_read_lock){....}-{1:2}, at: ieee80211_iterate_stations_atomic+0x2f/0x200 [mac80211]
CPU: 3 UID: 0 PID: 2236 Comm: iw Not tainted 6.11.0-rc7-wt-ath+ #1772
Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021
Call Trace:
<TASK>
dump_stack_lvl+0xa4/0xe0
dump_stack+0x10/0x20
__might_resched+0x363/0x5a0
? __alloc_skb+0x165/0x340
__might_sleep+0xad/0x160
ath12k_wmi_cmd_send+0xb1/0x3d0 [ath12k]
? ath12k_wmi_init_wcn7850+0xa40/0xa40 [ath12k]
? __netdev_alloc_skb+0x45/0x7b0
? __asan_memset+0x39/0x40
? ath12k_wmi_alloc_skb+0xf0/0x150 [ath12k]
? reacquire_held_locks+0x4d0/0x4d0
ath12k_wmi_set_peer_param+0x340/0x5b0 [ath12k]
ath12k_mac_disable_peer_fixed_rate+0xa3/0x110 [ath12k]
? ath12k_mac_vdev_stop+0x4f0/0x4f0 [ath12k]
ieee80211_iterate_stations_atomic+0xd4/0x200 [mac80211]
ath12k_mac_op_set_bitrate_mask+0x5d2/0x1080 [ath12k]
? ath12k_mac_vif_chan+0x320/0x320 [ath12k]
drv_set_bitrate_mask+0x267/0x470 [mac80211]
ieee80211_set_bitrate_mask+0x4cc/0x8a0 [mac80211]
? __this_cpu_preempt_check+0x13/0x20
nl80211_set_tx_bitrate_mask+0x2bc/0x530 [cfg80211]
? nl80211_parse_tx_bitrate_mask+0x2320/0x2320 [cfg80211]
? trace_contention_end+0xef/0x140
? rtnl_unlock+0x9/0x10
? nl80211_pre_doit+0x557/0x800 [cfg80211]
genl_family_rcv_msg_doit+0x1f0/0x2e0
? genl_family_rcv_msg_attrs_parse.isra.0+0x250/0x250
? ns_capable+0x57/0xd0
genl_family_rcv_msg+0x34c/0x600
? genl_family_rcv_msg_dumpit+0x310/0x310
? __lock_acquire+0xc62/0x1de0
? he_set_mcs_mask.isra.0+0x8d0/0x8d0 [cfg80211]
? nl80211_parse_tx_bitrate_mask+0x2320/0x2320 [cfg80211]
? cfg80211_external_auth_request+0x690/0x690 [cfg80211]
genl_rcv_msg+0xa0/0x130
netlink_rcv_skb+0x14c/0x400
? genl_family_rcv_msg+0x600/0x600
? netlink_ack+0xd70/0xd70
? rwsem_optimistic_spin+0x4f0/0x4f0
? genl_rcv+0x14/0x40
? down_read_killable+0x580/0x580
? netlink_deliver_tap+0x13e/0x350
? __this_cpu_preempt_check+0x13/0x20
genl_rcv+0x23/0x40
netlink_unicast+0x45e/0x790
? netlink_attachskb+0x7f0/0x7f0
netlink_sendmsg+0x7eb/0xdb0
? netlink_unicast+0x790/0x790
? __this_cpu_preempt_check+0x13/0x20
? selinux_socket_sendmsg+0x31/0x40
? netlink_unicast+0x790/0x790
__sock_sendmsg+0xc9/0x160
____sys_sendmsg+0x620/0x990
? kernel_sendmsg+0x30/0x30
? __copy_msghdr+0x410/0x410
? __kasan_check_read+0x11/0x20
? mark_lock+0xe6/0x1470
___sys_sendmsg+0xe9/0x170
? copy_msghdr_from_user+0x120/0x120
? __lock_acquire+0xc62/0x1de0
? do_fault_around+0x2c6/0x4e0
? do_user_addr_fault+0x8c1/0xde0
? reacquire_held_locks+0x220/0x4d0
? do_user_addr_fault+0x8c1/0xde0
? __kasan_check_read+0x11/0x20
? __fdget+0x4e/0x1d0
? sockfd_lookup_light+0x1a/0x170
__sys_sendmsg+0xd2/0x180
? __sys_sendmsg_sock+0x20/0x20
? reacquire_held_locks+0x4d0/0x4d0
? debug_smp_processor_id+0x17/0x20
__x64_sys_sendmsg+0x72/0xb0
? lockdep_hardirqs_on+0x7d/0x100
x64_sys_call+0x894/0x9f0
do_syscall_64+0x64/0x130
entry_SYSCALL_64_after_
---truncated---