[DirectX] Update lifetime intrinsic legalization after the removal of the size argument

[Icohedron]

Due to #150248, the following DirectX CodeGen tests are failing due to lifetime intrinsic function signature not matching what is expected by FileCheck.

  LLVM :: CodeGen/DirectX/ShaderFlags/lifetimes-noint64op.ll
  LLVM :: CodeGen/DirectX/legalize-lifetimes-valver-1.5.ll
  LLVM :: CodeGen/DirectX/legalize-lifetimes-valver-1.6.ll
  LLVM :: CodeGen/DirectX/legalize-memset.ll

These tests need to be updated to support the new lifetime intrinsic signature which now lacks the size argument.

Furthermore, the EmbedDXILPass' legalization of lifetime intrinsics (#150100) will need to be updated to re-add the size argument required by LLVM 3.7 / DXIL.