libgo: Generate dependencies automatically.

From-SVN: r181955
diff --git a/libgo/configure.ac b/libgo/configure.ac
index 62d4c95..6cb5f90 100644
--- a/libgo/configure.ac
+++ b/libgo/configure.ac
@@ -117,6 +117,11 @@
 AC_SUBST(LIBFFI)
 AC_SUBST(LIBFFIINCS)
 
+# Used to tell GNU make to include a file without telling automake to
+# include it.
+go_include="-include"
+AC_SUBST(go_include)
+
 is_darwin=no
 is_freebsd=no
 is_irix=no