wifi: iwlwifi: mld: track channel_load_not_by_us

For each channel context, track the avarage channel load by others in the
driver specific phy data, to be used by EMLSR.
Due to FW limitations, this value is incorrect in EMLSR, so it is
shouldn't be used in EMLSR.
On EMLSR exit, clear it so the wrong value won't be used.

Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Link: https://patch.msgid.link/20250309073442.dd443fc5b178.I68b2fed197aae14888159b7a73bf40c2f346f41f@changeid


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