This functions doesn't modify instance state, so it can be a made a
const member function.

Uses the same type aliases we use for virtual addresses, and converts
one lingering usage of std::array<uint64_t, 2> to u128 for consistency.

Note that there's currently a dynarmic bug preventing this register from being written.

Changes: Primarily implementing more A64 instructions

This makes clang-format useful on those.

Also add a bunch of forgotten transitive includes, which otherwise
prevented compilation.

The TLS area for thread T with id Ti is located at TLS_AREA_VADDR + (Ti - 1) * 0x200.
This allows some games like Mario Kart 7 to continue further.

Removes a TODO.

* Simplifies scheduling logic, specifically regarding thread status. It should be much clearer which statuses are valid
for a thread at any given point in the system.
* Removes dead code from thread.cpp.
* Moves the implementation of resetting a ThreadContext to the corresponding core's implementation.

Other changes:
* Fixed comments in arm interfaces.
* Updated comments in thread.cpp
* Removed confusing, useless, functions like MakeReady() and ChangeStatus() from thread.cpp.
* Removed stack_size from Thread. In the CTR kernel, the thread's stack would be allocated before thread creation.

This will keep track of idle ticks for us, and fixes some tickcount-related issues

- Also a few cleanups.