packagedata: Show error when trying to change PE/PV/PR from runtime/pkgdata
PN/PE/PV/PR should never change between do_package and the following do_package_write_*
tasks. If any do change you would see build failure due to the wrong WORKDIR being
used for example.
This patch ensures that if something is going wrong we see the error earlier and
with some better warning about what the real problem is.
[YOCTO #4102 partial]
This is a rewritten version of a patch from Martin Jansa <martin.jansa@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
