[ARM][MVE] validForTailPredication insts

Reverse the logic for valid tail predication instructions and create
a whitelist instead. Added other instruction groups that aren't
obviously safe:
- instructions that 'narrow' their result.
- lane moves.
- byte swapping instructions.
- interleaving loads and stores.
- cross-beat carries.
- top/bottom instructions.
- complex operations.

Hopefully we should be able to add more of these instructions to the
whitelist, once we have a more concrete idea of the transform.

Differential Revision: https://reviews.llvm.org/D67904

llvm-svn: 374887

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