Update resource type names for globals variables that we generate in `DXILTranslateMetadata` pass to include element type. This change prevents duplicate types for identical resources and brings the DXIL metadata names it closer to what DXC generates.

Use resource names gathered during the DXIL resource analysis when creating DXIL resources metadata.

Part 4/4 of https://github.com/llvm/llvm-project/issues/105059

Closes #105059

Adds resource name argument to `llvm.dx.handlefrombinding` and `llvm.dx.handlefromimplicitbinding` intrinsics.
SPIR-V currently does not seem to need the resource names so this change only affects DirectX binding intrinsics.

Part 2/4 of https://github.com/llvm/llvm-project/issues/105059

Adds checks for resource globals that were created for DXIL metadata.
The names of the globals and the names of the types will be changing
soon. Adding these to the baseline will make it easier to see what is
changing.

If these are constants their initializers will be removed by
InstCombine. Change them to not be constants and initialize them with
poison.

Update resource metadata tests to generate metadata based on
`llvm.dx.resource.handlefrombinding` data collected in
`DXILResourceBindingAnalysis`.

- `UAVMetadata.ll` is updated, renamed to `uav_metadata.ll`, and placed
under `Metadata` directory in `llvm/test/CodeGen/DirectX`
- `srv_metadata.ll` is a new test for SRV resource metadata
- `cbuf.ll` and `legacy_cb_layout_{0|1}.ll` tests were merged into
`cbuffer_metadata.ll`
- `legacy_cb_layout_{2|3}.ll` tests we moved to `cbuffer.hlsl` in Clang
CodeGen because there were more of a layout than metadata tests

Related to [#114126](https://github.com/llvm/llvm-project/issues/114126)

When some resource types were present, but not all of them, we were
ending up in a situation where we would fail to initialize the `FirstX`
variables and get incorrect iterators.

Fixes #128560.

Rename HLSL resource-related intrinsics to be consistent with the naming
conventions discussed in [wg-hlsl:0014].

This is an entirely mechanical change, consisting of the following
commands and automated formatting.

```sh
git grep -l handle.fromBinding | xargs perl -pi -e \
  's/(dx|spv)(.)handle.fromBinding/$1$2resource$2handlefrombinding/g'
git grep -l typedBufferLoad_checkbit | xargs perl -pi -e \
  's/(dx|spv)(.)typedBufferLoad_checkbit/$1$2resource$2loadchecked$2typedbuffer/g'
git grep -l typedBufferLoad | xargs perl -pi -e \
  's/(dx|spv)(.)typedBufferLoad/$1$2resource$2load$2typedbuffer/g'
git grep -l typedBufferStore | xargs perl -pi -e \
  's/(dx|spv)(.)typedBufferStore/$1$2resource$2store$2typedbuffer/g'
git grep -l bufferUpdateCounter | xargs perl -pi -e \
  's/(dx|spv)(.)bufferUpdateCounter/$1$2resource$2updatecounter/g'
git grep -l cast_handle | xargs perl -pi -e \
  's/(dx|spv)(.)cast.handle/$1$2resource$2casthandle/g'
```

[wg-hlsl:0014]: https://github.com/llvm/wg-hlsl/blob/main/proposals/0014-consistent-naming-for-dx-intrinsics.md

We need to create symbols with "the original shape of resource and
element type" to put in the resource metadata in order to generate valid
DXIL.

Note that DXC generally doesn't emit an actual symbol outside of library
shaders (it emits an undef of a pointer to the type), but since we have
to deal with opaque pointers we would need a way to smuggle the type
through to match that. Instead, we simply emit symbols for now.

Fixed #116849