[0035] LinAlg Matrix DXIL enum naming

[tex3d]

hlsl-specs/proposals/0035-linalg-matrix.md

Line 952 in eaa900c

enum class DXILMatrixUse {

This spec defines DXIL enumerations: DXILMatrixUse, DXILMatrixScope, and DXILComponentType. There are a couple issues with this:

DXIL enumerations are already defined under a DXIL namespace, so adding DXIL to the name is redundant.

There already exists a DXIL::ComponentType, and it already contains the new types referenced in this enum, only with different enum values. This existing enum is already used in a number of places in DXIL and the runtime interface, and it was originally the intention to use the same enum for matrix component types, otherwise we will have a higher likelihood of bugs and confusion. The existing type to numeric mappings already shipped in prior versions of DXIL cannot be changed without breaking DXIL.

We should not introduce another almost-identical enum with conflicting values just for this feature.

See in DXC:
https://github.com/microsoft/DirectXShaderCompiler/blob/201a5b598caed7158c0ea2aadf1a6e1590afa218/include/dxc/DXIL/DxilConstants.h#L164-L193

enum class ComponentType : uint32_t {
  ...

See in llvm-project:
https://github.com/llvm/llvm-project/blob/66da12ae69757690dff48e4c43816c753797babd/llvm/include/llvm/Support/DXILABI.h#L59-L80

See llvm/llvm-project#167784 for tangent on the ElementType name used here.

[tex3d]

Note, there are multiple copies of the ComponentType equivalent enumeration that all need to be synchronized with the existing ComponentType defined in DxilConstants.h in DXC.

HLSL Header snippet under HLSL API Documentation / HLSL Enumerations:

hlsl-specs/proposals/0035-linalg-matrix.md

Lines 475 to 478 in eaa900c

	#### HLSL Enumerations
	```c++
	struct ComponentType {
	enum ComponentEnum {

Under DXIL Types:

hlsl-specs/proposals/0035-linalg-matrix.md

Line 964 in eaa900c

enum class DXILComponentType {

For HLSL Header under Appendix 2: HLSL Header:

hlsl-specs/proposals/0035-linalg-matrix.md

Lines 1419 to 1420 in eaa900c

	struct ComponentType {
	enum ComponentEnum {