resources: remove outdated simple/README.md

Its information was moved into the toplevel README during review, but this
file was forgotten.

Change-Id: I9a876270f236d8b7131e6243ae79e382ea9240d6
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-resources/+/36675
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
tree: 97764d8dc0cbb2516e3592bb42b59ae236fb10f4
  1. README.md
  2. src/