In this case thread_sched_switch0 never returns, so we would never
end up setting finished to true.

Fixes [Bug #20638]

Use PR_SET_VMA_ANON_NAME to set human-readable names for anonymous
virtual memory areas mapped by `mmap()` when compiled and run on Linux
5.17 or higher.  This makes it convenient for developers to debug mmap.

The M:N threading stack cleanup machinery tries to call MADV_FREE on the native
thread's stack, and calls rb_bug if it fails. Unfortunately, there's no way to
distinguish between "You passed bad parameters to madvise" and "MADV_FREE is
not supported on the kernel you are running on"; both cases just return EINVAL.
This means that if you have a Ruby on a system that was built on a system with
MADV_FREE and run it on a system without it, you get a crash in nt_free_stack.

I ran into this because rr actually emulates MADV_FREE by just returning EINVAL
and pretending it's not supported (since it can otherwise introduce
nondeterministic behaviour). So if you run bootstraptest/test_ractor.rb under
rr, you get this crash.

I think we should just get rid of the error handling here; freeing memory like
this is strictly optional anyway.

[Bug #20632]

Introduce `struct rb_thread_sched_waiting` and `timer_th.waiting`
can contain other than `rb_thread_t`.

Signed-off-by: cui fliter <imcusg@gmail.com>

Introduce `rb_thread_lock_native_thread()` to allocate dedicated
native thread to the current Ruby thread for M:N threads.
This C API is similar to Go's `runtime.LockOSThread()`.

Accepted at https://github.com/ruby/dev-meeting-log/blob/master/2023/DevMeeting-2023-08-24.md
(and missed to implement on Ruby 3.3.0)

```
compiling ../thread.c
In file included from ../thread.c:263:
In file included from ../thread_pthread.c:2870:
../thread_pthread_mn.c:777:43: warning: format specifies type 'unsigned long' but the argument has type 'rb_hrtime_t' (aka 'unsigned long long') [-Wformat]
		RUBY_DEBUG_LOG("abs:%lu", abs);
				    ~~~   ^~~
				    %llu
../vm_debug.h:110:74: note: expanded from macro 'RUBY_DEBUG_LOG'
	ruby_debug_log(__FILE__, __LINE__, RUBY_FUNCTION_NAME_STRING, "" __VA_ARGS__); \
									 ^~~~~~~~~~~
1 warning generated.
```

In a similar way to how we do it with fibers in cont.c, we need to call
__sanitize_start_switch_fiber and __sanitize_finish_switch_fiber around
the call to coroutine_transfer to let ASAN save & restore the fake stack
pointer.

When a M:N thread is exiting, we pass `to_dead` to the new
coroutine_transfer0 function, so that we can pass NULL for saving the
stack pointer. This signals to ASAN that the fake stack can be freed
(otherwise it would be leaked)

[Bug #20220]