website: Update example command-lines in building_arm_kernel

* Deprecate fs.py from the example command-lines in favour of
starter_fs.py

* Point to a more up to date disk image

Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: Id4897466c8d023136c35bc5596a2b6f33acbc0d7
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-website/+/43183
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: Bobby R. Bruce <bbruce@ucdavis.edu>
1 file changed