adapt to latest libfirm

[cparser] / libfirm

diff --git a/libfirm b/libfirm
index ab4e272..5609f2c 160000 (submodule)
--- a/libfirm
+++ b/libfirm
@@ -1 +1 @@
-Subproject commit ab4e27261cf300c01cae065f4d48f54e664da8f1
+Subproject commit 5609f2c7223b8482d8c2d9d79163608e6eec7cc0