wifi: mac80211: Make CONNECTION_MONITOR optional for MLO sta

Since commit '1bc892d7 ("wifi: mac80211: extend connection
monitoring for MLO")' mac80211 supports connection monitor for MLO
client interfaces. Remove the CONNECTION_MONITOR requirement in
ieee80211_register_hw routine.

Fixes: 1bc892d7 ("wifi: mac80211: extend connection monitoring for MLO")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20250826-remove-conn-mon-check-ieee80211_register_hw-v2-1-5a1e2f038245@kernel.org


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