iwlwifi: mvm: clean up authorized condition

We track in mvmvif->authorized when the AP STA becomes authorized
and no longer authorized, so we don't need the complex condition
with station lookup. Simplify the code.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20220517120044.41f528383a6b.I1cdf165581b781c53c8e6ac8779a2282b1f67c59@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>