mac80211: remove duplicate check for quiescing when queueing work

In ieee80211_queue_work() we check if we're quiescing or suspended, so
it's not necessary to check for quiescing before calling this
function.  Remove duplicate checks.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>