The unihash should be fetched using the task filename that includes the
multiconfig prefixes.
[YOCTO #13124]
(Bitbake rev: 5e7f4e77e27bceaf6c68137cacb4f8d7d7de49dd)
Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>