webiste: Update tarball to aarch-system-20210904.tar.bz2

Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: Ifee9a7ebe81ee88f4b23600ccf37fb2873434f34
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-website/+/44327
Reviewed-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: Bobby R. Bruce <bbruce@ucdavis.edu>
diff --git a/_pages/documentation/general_docs/fullsystem/guest_binaries.md b/_pages/documentation/general_docs/fullsystem/guest_binaries.md
index 903130b..4432ace 100644
--- a/_pages/documentation/general_docs/fullsystem/guest_binaries.md
+++ b/_pages/documentation/general_docs/fullsystem/guest_binaries.md
@@ -25,7 +25,7 @@
 
 The tarball below contains a set of binaries: the Linux kernel and a set of bootloaders
 
-* <http://dist.gem5.org/dist/current/arm/aarch-system-201901106.tar.bz2>
+* <http://dist.gem5.org/dist/v21-0/arm/aarch-system-20210904.tar.bz2>
 
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