Revert "mac80211: allow using AP_LINK_PS with mac80211-generated TIM IE"

This reverts commit c68df2e7.

__sta_info_recalc_tim turns into a no-op if local->ops->set_tim is not
set. This prevents the beacon TIM bit from being set for all drivers
that do not implement this op (almost all of them), thus thoroughly
essential AP mode powersave functionality.

Cc: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Fixes: c68df2e7 ("mac80211: allow using AP_LINK_PS with mac80211-generated TIM IE")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>