stdlib: Update the LupvBoard to use KernelDiskWorkload Change-Id: I5857f70e6ca61b8916792e634d20cdf827b21bd0 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/53085 Maintainer: Bobby Bruce <bbruce@ucdavis.edu> Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>