The x86-boot-exit resource is being deprecated for the more versatile x86-ubuntu-img resource. The latter attempts to run `m5 readfile`, allowing a user to specify a script to be run. If no script is specified `m5 exit` is run. Therefore it can be used in the x86-boot-exit tests. Change-Id: I7fecb314bd0e1d4be4f1181e57046e4621199b64 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/50647 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Austin Harris <mail@austin-harris.com> Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>