Currently compiling a new package and adding it
to the iso still requires a multi-git update because
image.inc is a single centralized file in the root git.
It would be better to allow a single git update to add
a package. Too allow this, image.inc must be split across
the git repos and the build tools must be changed to
read/merge those files to arrive at the final package list.
Current scheme is to name the image.inc files using this
schema.
${distro}_${build_target}_image_${build_type}.inc
distro = centos, ...
build_target = iso, guest ...
build_type = std, rt ...
Traditionally build_type=std is omitted from config files,
so we instread use ${distro}_${build_target}_image.inc.
Story: 2003447
Task: 24650
Change-Id: Ib39b8063e7759842ba15330c68503bfe2dea6e20
Signed-off-by: Scott Little <scott.little@windriver.com>