iwlwifi: mvm: Add basic uAPSD client support

iwlwifi: mvm: Add basic uAPSD client support

Implement basic uAPSD client support adding the following:

- Advertise uAPSD support in HW capabilities
- Set all ACs trigger- and delivery-enabled
- Set max SP length to 2 buffered frames
- Assign QNDP with the highest TID with no mandatory admission
  control required
- Set uAPSD related parameters in Power Table command

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>