Make minor improvements to super

The changes here include:

* Using `FL_TEST_RAW` instead of `FL_TEST` in the first check in
`vm_search_super_method`. While the profile showed us spending a fair
amount of time here, the subsequent benchmarks didn't show much
improvement when adding this. Regardless, we know this does less work
than `FL_TEST` and we know that `FL_TEST_RAW` is safe due to the
previous check so it's a small but accurate optimization.
* Set `mid` only once. Both `vm_ci_new_runtime` and `vm_ci_mid` were
getting the `original_id` for the method entry. We can do this once
and pass the variable to the 2 callers that need it. This also doesn't
have a huge performance improvement but cleans up the code a bit.

Benchmark:

```
|                 |compare-ruby|built-ruby|
|:----------------|-----------:|---------:|
|vm_iclass_super  |      3.540M|    3.940M|
|                 |           -|     1.11x|
```

Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org>

0 files changed, 0 insertions, 0 deletions