[SPIRV][DirectX][HLSL] Move `cross` implementation to hlsl_intrinsics.h

[farzonl]

1. Remove Intrinsic::dx_cross
2. Remove BI__builtin_hlsl_cross
3. Remove BI__builtin_hlsl_cross Sema checks from clang/lib/Sema/SemaHLSL.cpp
4. Remove getCrossIntrinsic from clang/lib/CodeGen/CGHLSLRuntime.h
5. Remove emitting intrinsic from clang/lib/CodeGen/CGBuiltin.cpp
6. Remove expandCrossIntrinsic in llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp
7. Implement cross algorithmicly in hlsl_intrinsics.h
8. add a pattern match for cross as an InstCombine in llvm/lib/Target/SPIRV/SPIRVPreLegalizerCombiner.cpp to be able to still emit the cross GL extension.