website: Added GCC version information for v20.1

Change-Id: Iaff86844602b33851dce0d2bde3717ba5ea1d954
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-website/+/33657
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: Bobby R. Bruce <bbruce@ucdavis.edu>
2 files changed