remove obsolete Nyacc link.

* guile/nyacc: Remove.

diff --git a/guile/nyacc b/guile/nyacc
deleted file mode 120000 (symlink)
index cb67913..0000000
--- a/guile/nyacc
+++ /dev/null
@@ -1 +0,0 @@
-../module/nyacc
\ No newline at end of file