dontdiff: add modules.order

Add modules.order to the list of files that
shoud be ignored when using diff on a built
kernel tree.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Documentation/dontdiff

@@ -141,6 +141,7 @@ mkprep
 mktables
 mktree
 modpost
+modules.order
 modversions.h*
 offset.h
 offsets.h