Set home to /root when running build time services

This change follows what we did for the post build checks
in commit ae05363.

Fixes #901

build

@@ -1799,7 +1799,7 @@ for RECIPEPATH in "${RECIPEFILES[@]}" ; do
 
     if  test -e _service; then
 	echo "Running build time source services..."
-	$BUILD_DIR/runservices --buildroot "$BUILD_ROOT" || cleanup_and_exit 1
+	HOME=/root $BUILD_DIR/runservices --buildroot "$BUILD_ROOT" || cleanup_and_exit 1
     fi
 
     # get rid of old src dir, it is no longer needed and just wastes space