mac80211: Suppress NEW_PEER_CANDIDATE event if no room

[ Upstream commit 11197d006bcfabf0173a7820a163fcaac420d10e ]

Previously, kernel sends NEW_PEER_CANDIDATE event to user land even if
the found peer does not have any room to accept other peer. This causes
continuous connection trials.

Signed-off-by: Masashi Honma <masashi.honma@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>