resources: Fixed square build documentation

Square needs to be built via the `gcn-gpu` docker image. Previously the
README.md falsely claimed it could be built by installing the ROCM
compiler.

This commit also cleans-up the `src/square/Makefile` and added the
`src/square/bin` directory to `src/square/.gitignore`.

Change-Id: Ia808e2a2d1c15d51e7eec8e76d77705a07dd9bf8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-resources/+/33555
Reviewed-by: Kyle Roarty <kyleroarty1716@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: Jason Lowe-Power <power.jg@gmail.com>
3 files changed
tree: 7c44b3a4da9c4f36c537807e8ebfce4800d8908e
  1. .gitignore
  2. README.md
  3. src/