scons: Re-enable override based warnings on gcc.

These warnings have been fixed.

Change-Id: I28ee5f4ae21412121849fcb9d273939d8e462842
Reviewed-on: https://gem5-review.googlesource.com/9344
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
1 file changed