Applications can request the kernel to allocate a piece of the linear heap for them when creating a shared memory object.
Shared memory areas are now properly mapped into the target processes when calling svcMapMemoryBlock.

Removed the APT Shared Font hack as it is no longer needed.

Modifying a variable twice across a sequence point.

with a stub for GetSoundVolume

Removes a TODO.

This coincidentally fixes an issue about the PTM service failing to create its SharedExtSaveData archive due to the FS service not being initialized by the time the creating code runs.

Ideally I'd like to move each process to its own folder, and have a single file per process that registers the service classes, which would be in their own files inside that folder. Then each service class would just call functions from the process to complete the commands.

They're finally unnecessary, and will stop cluttering the application's
handle table.