* Drop buildroot from git repository
Manage buildroot in a separate git repository and use a git submodule
to include it into the HAOS source tree.
This makes it easier to manage changes to buildroot since it can be
managed by git. A buildroot fork repository is being maintained with
the changes we currently have. It makes the buildroot-patches unnecessary
and should make it easier to rebase and upstream changes to buildroot.
* Remove buildroot-patches
Now that buildroot changes are managed in the buildroot fork repository
there is no need to manage patches in a separate directory.
* Initialize git submodule if necessary
* Move build directory to root
This avoids conflict/local modification issues with the buildroot
git submodule.
