tests: Add test to check disconnect in powersave

The kernel had two bugs (one in hwsim and one more important one in
mac80211) in this area, add a test to make sure we can disconnect
without any kernel issues while in powersave.

Also make sure that the TIM bit gets set and cleared again (by checking
with tshark.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2 files changed