Update public function documentation for Map Client

This change inherits the documentation from the parent class definitions
where it can, so our profile proxy can be more in line with others.

Ignore-AOSP-First: Mainline-related going into internal first
Tag: #refactor
Bug: 221881179
Test: atest BluetoothInstrumentationTests
Change-Id: Ied98b70ea8fb698c576a43c09ba384698bb78233