[HLSL] Add Descriptor Table element support to dxcontainer generation

[joaosaffran]

Descriptor Table need to be extracted, validated and added into DXContainer Root Signature representation.

AC:

• Update a Root Signature analysis pass to extract element metadata from LLVM IR.
• Add validation stage to check extracted data.
• Add error handling to invalid data and invalid metadata scenarios.
• Add test to check the generated data and validations are executed correctly.