[TF-M] Applying stateless handle to built-in services

Hi,

Shawn is applying stateless handle to built-in services, here are the patches for reviewing: https://review.trustedfirmware.org/q/topic:%22Apply_stateless_handle%22+(sta...)

Only those services are really STATELESS can be applied with stateless handle. For the legacy connection-based services (supports multiple sessions), please keep using the connect/call/close based mechanism when accessing services.

Thanks.

/Ken