[llvm-exegesis] move Mode from Key to BenchmarResult.

Moves the Mode field out of the Key. The existing yaml benchmark results can be fixed with the following script:

```
readonly FILE=$1
readonly MODE=latency # Change to uops to fix a uops benchmark.
cat $FILE | \
  sed "/^\ \+mode:\ \+$MODE$/d" | \
  sed "/^cpu_name.*$/i mode:            $MODE"
```

Differential Revision: https://reviews.llvm.org/D47813

Authored by: Guillaume Chatelet

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@334079 91177308-0d34-0410-b5e6-96231b3b80d8
10 files changed