fixed typo

cl_decomp3d.py

@@ -10,7 +10,7 @@ ng = int(sys.argv[2])
 if len(sys.argv) > 3:
     maxAspectRatio = float(sys.argv[3])
 else:
-    maxAspectRation = 0.0
+    maxAspectRatio = 0.0
 
 decompList = D.filterNgNranks(ng, nranks, maxAspectRatio)