checkpatch.conf: Exclude machine-generated file library/DIAMETER_Types.ttcn from linter

Change-Id: Iff72ddabea41b36d30a7ad87218aa68b1297c35e
diff --git a/.checkpatch.conf b/.checkpatch.conf
index 0882941..700e952 100644
--- a/.checkpatch.conf
+++ b/.checkpatch.conf
@@ -1 +1,2 @@
 --exclude ^library/sbcap/.*\.asn$
+--exclude ^library/DIAMETER_Types.ttcn$