website: Updated image URLs to img.gz

In efforts to reduce storage costs, gem5 images have been gzipped. URLs
in the website have therefore been updated accordingly.

We've also added the .img extension to make it clearer as to what what
these files are.

Change-Id: I062e6e42c8aa578c95817c7a100869051f634985
Maintainer: Bobby R. Bruce <>
Reviewed-by: Jason Lowe-Power <>
Tested-by: Jason Lowe-Power <>
2 files changed