tests: Update the documentation in compiler-tests.sh

This was out-of-date and has been updated in this commit.

Change-Id: I18519bb2111dae4d2f86806618115153fa8d5372
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47339
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
1 file changed