wifi: iwlwifi: mvm: rename iwl_dev_tx_power_common::mac_context_id

wifi: iwlwifi: mvm: rename iwl_dev_tx_power_common::mac_context_id

This is becoming the link_id. Since this makes no difference on non-MLD
devices, just rename to link_id for all the APIs that use the common
structure.

Starting from command 9, feed the link_id to the firmware instead of the
mac id.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20241227095718.f1155e713201.I753900d10e82f339cf9679ed403027d38dc1fd58@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>