Patch allows to build shared library on kfreebsd-* architectures.

Index: tclreadline-2.1.0/aux/ltconfig
===================================================================
--- tclreadline-2.1.0.orig/aux/ltconfig
+++ tclreadline-2.1.0/aux/ltconfig
@@ -1984,7 +1984,7 @@
   ;;
 
 # This must be Linux ELF.
-linux-gnu*)
+linux-gnu*|kfreebsd*-gnu*)
   version_type=linux
   need_lib_prefix=no
   need_version=no