Change PROMISE target to CPU target

...ib/Transforms/DFG2LLVM_WrapperAPI/DFG2LLVM_WrapperAPI.cpp

...ib/Transforms/FuseHPVMTensorNodes/FuseHPVMTensorNodes.cpp

hpvm/lib/Transforms/GenVISC/CMakeLists.txt

hpvm/lib/Transforms/GenVISC/GenHPVM.cpp

hpvm/lib/Transforms/GenVISC/GenHPVM.exports

hpvm/lib/Transforms/GenVISC/LLVMBuild.txt