The logic is scattered all over the place, but amounts to
"install, unless the rootfs is read only". Let's express that directly.
(From OE-Core rev: 697804229a172125ce7d3bfc9b343812d6fe3240)
Signed-off-by: Alexander Kanavin <alexander.kanavin@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>