Whilst this needs renaming it at least brings this image into
line with the other images and ensures consistent behaviour.
Renaming can take place at a future point.
This fixes the problem where extra packages could be added to other
image types using this varibale but not in the case of the minimal
image.
(From OE-Core rev: 8df322abfd3fa8c460fd73c83c1ef0b5e419dc11)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
ce66e2c6bd