scons: Stop the fast model project file parser from writing files.

PLY tries to write these little files into the SCons installation
directory, which it shouldn't even if it was allowed to. This avoids
a bunch of annoying messages about not having enough permission.

Change-Id: Ifd4eda9dd9f8518b3fd075e8a46de1b6c12c2127
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/58353
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jui-min Lee <fcrh@google.com>

SConstruct

@@ -85,6 +85,9 @@ from os.path import abspath, dirname, expanduser
 from os.path import isdir, isfile
 from os.path import join, split
 
+import logging
+logging.basicConfig()
+
 # SCons imports
 import SCons
 import SCons.Node