Add llvm.fabs intrinsic (generated by LLVM 3.8)
Add llvm.fabs intrinsic (generated by LLVM 3.8)

surround-io/oclgrind,mpflanzer/Oclgrind,surround-io/oclgrind,surround-io/oclgrind,mpflanzer/Oclgrind,surround-io/oclgrind,mpflanzer/Oclgrind,mpflanzer/Oclgrind