[AVX] Make TernOpInit Unique
[AVX] Make TernOpInit Unique

Make sure TernOpInits are unique and created only once.  This will be
important for AVX/SIMD as many operators will be used to generate
patterns and other relevant data.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@136496 91177308-0d34-0410-b5e6-96231b3b80d8

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