stdlib,configs,tests: Rename config to arm-ubuntu-run.py

The "config/example/gem5_library/arm-ubuntu-boot-exit.py" script is
renamed to "config/example/gem5_library/arm-ubuntu-run.py". This makes
it more consistent with similar scripts in the
"config/example/gem5_library" directory: "x86-ubuntu-run.py" and
"riscv-ubuntu-run.py".

Change-Id: I9d96fd68e122f2841573b1717b0969cd44972771
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/65132
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
2 files changed