message: alloy.py: make unsupported_llvm_targets() more robust
diff: @@ -429,13 +429,10 @@ def unsupported_llvm_targets(LLVM_VERSION):
  "3.4":["avx512knl-i32x16", "avx512skx-i32x16"],
  "3.5":["avx512knl-i32x16", "avx512skx-i32x16"],
  "3.6":["avx512knl-i32x16", "avx512skx-i32x16"],
  - "3.7":["avx512skx-i32x16"],
  - "3.8":[],
  - "3.9":[],
  - "4.0":[],
  - "5.0":[],
  - "trunk":[]}
  + "3.7":["avx512skx-i32x16"]}
  + if LLVM_VERSION in prohibited_list:
  return prohibited_list[LLVM_VERSION]
  + return []
  # Split targets into categories: native, generic, knc, sde.
  