iwlwifi: mvm: register to mac80211 last

iwlwifi: mvm: register to mac80211 last

All the actions that were taken after the registration can
be taken before the registration to mac80211.
This will help to defer part of the op_mode_mvm_start
function to a later stage in case the device is not
available.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210210171218.c03cc5db67c1.Ia928ca34d25a73d959a345ffbe4f1217c3f17394@changeid
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>