wifi: iwlwifi: mvm: Refactor MAC_CONTEXT_CMD sending flow

Refactor MAC_CONTEXT_CMD sending flow:

1. As the new MLD API is introduced, there are some common fields in
both the old and new APIs. The MAC_CONTEXT_CMD of the non-MLD API
has common fields with the link and mac commands of the new MLD API.
Put this common parts in functions so it can be used later by the
new MLD API.

2. Use iwl_mvm_mac_ctxt_send_cmd when removing a mac instead of
implementing the same functionality once again.

3. Change the debug print when sending the command to be more specific,
so it will be easy to distinguish later if the old or new mac command
was sent.
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230314194113.3ab62700db4e.I2e353b308667c215aa456c160e0d90de2b9b85cc@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>