[llvm] [llvm-exegesis] Skip benchmark entries with unknown opcodes in analysis mode (PR #201162)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon commented:

How easy will it be to add the "did you mean...." helper? I want to make sure that any followup doesn't have to refactor all this code....

https://github.com/llvm/llvm-project/pull/201162