iwlwifi: mvm: Upgrade to a new power management uAPSD API

Change power management implementation to support new host-device API
containing uAPSD parameters. Verify FW support for this new API.
Use the new power table command (0xA9) to configure power management.
Use the legacy command (0x77) if FW does not support the new API.
New file power_legacy.c is introduced for legacy implementation.

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>