wifi: iwlwifi: mvm: fix narrow RU check for MLO

This needs to apply to the link, not deflink.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230329100039.0347fa77d522.Ibdf7a40cbe86e64ce086f243330fc27f43aeb3aa@changeid


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