feat(build_package): add build_tf_extra() helper function

It allows building any extra rule from TF-A makefile, which is useful
in case you need to build something else than firmware binaries or the
FIP.

Change-Id: Ie63d8b152762934561405de5937e44696ba4081a
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
1 file changed