tests: Move the bituniontest to be alongside the bitunion header.

Change-Id: I7c1a49c41672a1108fcf67c5505b0441f90588ef
Reviewed-on: https://gem5-review.googlesource.com/6142
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
3 files changed