[DirectX] Implement Shader Flag Analysis to collect properties of DML shaders

[bharadwajy]

DML Shaders in test suite of DirectML repo that are compiled using dxc (with designated command-line options in the test configuration) generate one or more of the following shader flags.

• [DirectX] Implement Shader Flags Analysis for Max64UAVs #114553
  This is a module-level flag. Set if number of UAVs used is > 8 - see here
• [DirectX] Implement Shader Flags Analysis for LowPrecisionPresent #114561
  Set if the candidate function uses an instruction with operands of llvm::Type::TypeID::HalfID or Int16Ty
• [DirectX] Implement Shader Flags Analysis for Int64Ops #114562
  Set if the candidate function uses an instruction with operands of type Int64Ty
• [DirectX] Implement Shader Flags Analysis for DX11_1_DoubleExtensions #114554
  Set if the candidate function calls the intrinsic DXIL::OpCode::Fma.
  NOTE: Code to set this flag if the function uses one of an instruction is one of the instructions Instruction::FDiv, Instruction::UIToFP, Instruction::SIToFP, Instruction::FPToUI or Instruction::FPToSI is already implemented.
• [DirectX] Implement Shader Flags Analysis for WaveOps #114565
  Set if the candidate function uses a DXIL WaveOp - see here

AC:
Add tests to verify collection of each of the flags.

[Icohedron]

@bogner mentioned that #120152 is not urgent and things seem to be working okay as they are now, so I will be moving this issue out to llvm/wg-hlsl#57