[HLSL] Semantic analysis of `HLSLRootSignature`

[inbelic]

This issue handles the additional semantic analysis of the parsed HLSLRootSignature attribute. This includes generating applicable diagnostics.

Semantic validation can be broken down into syntactical checks and validations done in sema, as defined in syntactical validation and in semantic validation.

The relevant validations that this issue will have implemented when both sub-issues are completed:

• Ensure valid values of DESCRIPTOR_RANGE_FLAGS for the Sampler descriptor table clause
• Ensure that some parameters of StaticSampler are bounded correctly
• Validate that the space parameter is not in the invalid range of 0xFFFFFFF0 to 0xFFFFFFFF
• Validate that resource ranges don't overlap
• Ensure that registers are only bound once
• Ensure that the correct register type matches the desriptor range type

This issue is completed when all sub-issues are completed.