Resolves #141955

- Adds data to breakpoints `Source` object, in order for assembly
breakpoints, which rely on a temporary `sourceReference` value, to be
able to resolve in future sessions like normal path+line breakpoints
- Adds optional `instructions_offset` parameter to `BreakpointResolver`

A DriverKit process is a kernel extension that runs in userland, instead
of running in the kernel address space/priv levels, they've been around
a couple of years. From lldb's perspective a DriverKit process is no
different from any other userland level process, but it has a different
Triple so we need to handle those cases in the lldb codebase. Some of
the DriverKit triple handling had been upstreamed to llvm-project, but I
noticed a few cases that had not yet. Cleaning that up.

Lots of code around LLDB was directly accessing the target's section
load list. This NFC patch makes the section load list private so the
Target class can access it, but everyone else now uses accessor
functions. This allows us to control the resolving of addresses and will
allow for functionality in LLDB which can lazily resolve addresses in
JIT plug-ins with a future patch.

This change enables `DynamicLoaderDarwin` to load modules in parallel
using the thread pool. This new behavior is controlled by a new setting
`plugin.dynamic-loader.darwin.experimental.enable-parallel-image-load`,
which is enabled by default. When disabled, DynamicLoaderDarwin will
load modules sequentially as before.

This patch removes all of the Set.* methods from Status.

This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.

This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()

Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form

`    ResultTy DoFoo(Status& error)
`
to

`    llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?

The interesting changes are in Status.h and Status.cpp, all other
changes are mostly

` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.

This upstreams the BridgeOS target triple enum value.

Upstream support for debugging xros applications through LLDB.

dyld has two notification functions - a native one, and one that
it rewrites its arguments for, for lldb.  We currently use the
latter, _dyld_debugger_notification.  The native notification
function, lldb_image_notifier (and on older systems, gdb_image_notifier)
we can find by name, or if libdyld shows no dyld loaded in the
process currently, we can get it from the dyld_all_image_infos
object in memory which we can find with a system call.  When we do
a "waitfor attach" to a process on a modern darwin system, there
is a transition early in launch from the launch dyld to the
shared-cache-dyld, and when we attach in the middle of that transition,
libdyld will say there is no dyld present.  But we can still find
the in-memory dyld_all_image_infos which has the address of the
shared cache notifier function that will be registered in the
process soon.

This change will result in a much more reliable waitfor-attach.

This is the third landing of this patch.  We have an Intel mac
CI bot that is running an older (c. 2019) macOS 10.15, I had to
reproduce that environment and found the name of the notifier
function had changed which was the cause of those failures.

Differential Revision: https://reviews.llvm.org/D139453
rdar://101194149

This reverts commit c3192196aea279eea0a87247a02f224ebe067c44.

Reverting my second attempt at https://reviews.llvm.org/D139453
changing which dyld notification method is being used.
The Intel macOS CI bot is still failing with this
rewrite at https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/
I'll need to set up an Intel macOS system running a matching
OS version to debug this directly I think.

On Darwin systems, the dynamic linker dyld has an empty function
it calls when binaries are added/removed from the process.  lldb puts
a breakpoint on this dyld function to catch the notifications.  The
function arguments are used by lldb to tell what is happening.

The linker has a natural representation when the addresses of
binaries being added/removed are in the pointer size of the process.
There is then a second function where the addresses of the binaries
are in a uint64_t array, which the debugger has been using before -
dyld allocates memory for the array, copies the values in to it,
and calls it for lldb's benefit.

This changes to using the native notifier function, with pointer-sized
addresses.

This is the second time landing this change; this time correct the
size of the image_count argument, and add a fallback if the
notification function "lldb_image_notifier" can't be found.

Differential Revision: https://reviews.llvm.org/D139453