simd_runtime_generate! broken in 1.01

[ronniec95]

Using that macro currently fails with

cannot find type `Avx` in this scoperustc(E0412)
avx2.rs(8, 1): similarly named struct `Avx2` defined here
lib.rs(111, 5): a struct with a similar name exists

Missing a few use and target_feature statements I noticed - I can submit a PR Also the compile_time macro doesn't generate avx - missing cfg()

[jackmott]

Apologies for that, give it a try in 1.0.2, if all is well you can go ahead and close.,

[ronniec95]

Great thank you