wifi: ath10k: Remove redundant assignment to changed_flags

Variable changed_flags is assigned, but is not effectively used, so
delete it.

drivers/net/wireless/ath/ath10k/mac.c:6024:22: warning: parameter 'changed_flags' set but not used.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3963
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230207052410.26337-1-jiapeng.chong@linux.alibaba.com