wifi: iwlwifi: mvm: init vif works only once

wifi: iwlwifi: mvm: init vif works only once

It's dangerous to re-initialize works repeatedly, especially
delayed ones that have an associated timer, and even more so
if they're not necessarily canceled inbetween. This can be
the case for these workers here during FW restart scenarios,
so make sure to initialize it only once.

While at it, also ensure it is cancelled correctly.

Fixes: f67806140220 ("iwlwifi: mvm: disconnect in case of bad channel switch parameters")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240416134215.ddf8eece5eac.I4164f5c9c444b64a9abbaab14c23858713778e35@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>