Use git submodule for buildroot (#1445)

* 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.

scripts/enter.sh

@@ -11,6 +11,11 @@ sudo mkdir -p "${CACHE_DIR}"
 sudo chown -R "${BUILDER_UID}:${BUILDER_GID}" "${CACHE_DIR}"
 sudo docker build -t hassos:local .
 
+if [ ! -f buildroot/Makefile ]; then
+  # Initialize git submodule
+  git submodule update --init
+fi
+
 # Make sure loop devices are present before starting the container
 sudo losetup -f > /dev/null
 

scripts/update-buildroot.sh

@@ -1,26 +0,0 @@
-#!/bin/bash
-set -e
-
-if [ -z "$1" ]; then
-    echo "Need a buildroot version!"
-    exit 1
-fi
-
-rm -rf /tmp/buildroot-new
-mkdir -p /tmp/buildroot-new
-
-echo "Download new buildroot"
-curl -L "https://buildroot.org/downloads/buildroot-${1}.tar.bz2" \
-    | tar xvpjf - --strip 1 -C /tmp/buildroot-new 
-
-echo "Install patches"
-for patch_file in buildroot-patches/*; do
-    echo "Patch: ${patch_file}"
-    patch -d /tmp/buildroot-new -p 1 < "${patch_file}";
-done
-
-rm -rf buildroot
-mv /tmp/buildroot-new buildroot
-
-git add buildroot
-git commit -sam "Update buildroot to ${1}"