Remove outdated passes

lib/DFG2LLVM_PROMISE/CMakeLists.txt

lib/DFG2LLVM_PROMISE/DFG2LLVM_PROMISE.cpp

lib/DFG2LLVM_PROMISE/DFG2LLVM_PROMISE.exports

lib/DFG2LLVM_PROMISE/LLVMBuild.txt

lib/DFG2LLVM_SPIR/CMakeLists.txt

lib/DFG2LLVM_SPIR/DFG2LLVM_SPIR.cpp

lib/DFG2LLVM_SPIR/DFG2LLVM_SPIR.exports

lib/DFG2LLVM_SPIR/LLVMBuild.txt

lib/InsertApproxInfo/CMakeLists.txt

lib/InsertApproxInfo/InsertApproxInfo.cpp

lib/InsertApproxInfo/LLVMBuild.txt

lib/MergeDFN/CMakeLists.txt

lib/MergeDFN/LLVMBuild.txt

lib/MergeDFN/MergeDFN.cpp

lib/MergeDFN/MergeDFN.exports