configs: fixed SimpleOpts missing error by adding library path

Change-Id: I0de761c8a322a506e436d5c7f12ee509535f52fd
Reviewed-on: https://gem5-review.googlesource.com/2801
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

configs/learning_gem5/part1/caches.py

@@ -33,9 +33,12 @@ This file contains L1 I/D and L2 caches to be used in the simple
 gem5 configuration script. It uses the SimpleOpts wrapper to set up command
 line options from each individual class.
 """
-
+import m5
 from m5.objects import Cache
 
+# Add the common scripts to our path
+m5.util.addToPath('../../')
+
 from common import SimpleOpts
 
 # Some specific options for caches