mac80211: ath: improve ath10k "failed to flush transmit queue" errors

mac80211: ath: improve ath10k "failed to flush transmit queue" errors

Currently, in busy environments, ath10k logs "failed to flush transmit
queue" errors and have a spiking CPU usage, making the wireless barely
usable.
With this patch, taken from https://patchwork.kernel.org/project/linux-wireless/patch/20250806070005[email protected]/
this does not occur in normal operation and the wifi is much more stable

Supersedes #19427
Ref: https://github.com/openwrt/openwrt/issues/15929#issuecomment-2227391307
Ref: https://github.com/openwrt/openwrt/issues/14965

Signed-off-by: Florian Maurer <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/19529
(cherry picked from commit ab50b9a56148767a5e364ad41b79e186c7eea8f4)
Link: https://github.com/openwrt/openwrt/pull/20266
Signed-off-by: Hauke Mehrtens <[email protected]>