ony authored Oct 26, 2015 and Ben Gamari committed Oct 26, 2015

- Add `-pgmreadelf` option
- Auto configure path and name of "readelf"
- Add settings `readelf command`
- During build of GHC name of tool can be changed with
  `./configure --with-readelf=myreadelf`

Test Plan:
```
make -C testsuite/tests/driver/recomp011
```

Reviewers: austin, bgamari

Subscribers: erikd, thomie

Differential Revision: https://phabricator.haskell.org/D1335

GHC Trac Issues: #10974