Revert #3013, Metasm update

This revert of #3013 addresses RM [#8775](https://dev.metasploit.com/redmine/issues/8775). cc @todb-r7 @jvazquez-r7

**Verification steps**:

- [ ] Make sure you're on the latest and greatest ```master```
- [ ] Create a development branch tracking ```master```
- [ ] Perform a test merge of the topic branch
- [ ] Ensure that Metasm is working like it was before (you can use the verification steps from #3013)

**Sample run**:

```
wvu@kharak:~/metasploit-framework:master$ git fetch --all
Fetching origin
Fetching upstream
wvu@kharak:~/metasploit-framework:master$ git reset --hard upstream/master
HEAD is now at c76c022 Land #3110, Set-Cookie check for msftidy
wvu@kharak:~/metasploit-framework:master$ git checkout -b dev -t master
Branch dev set up to track local branch master.
Switched to a new branch 'dev'
wvu@kharak:~/metasploit-framework:dev$ git merge --no-ff --no-edit beug/metasm
[snip]
wvu@kharak:~/metasploit-framework:dev$
```