knetbsd/kfreebsd patches from Robert Millan.

* libtool.m4: Add kfreebsd*-gnu and knetbsd*-gnu.
* ltconfig: Likewise.
* ltcf-c.sh: Likewise.
* ltcf-cxx.sh: Likewise.
* ltcf-gcj.sh: Likewise.

ltcf-cxx.sh

@@ -244,7 +244,7 @@ case $host_os in
     # C++ shared libraries reported to be fairly broken before switch to ELF
     ld_shlibs=no
     ;;
-  freebsd*)
+  freebsd* | kfreebsd*-gnu)
     # FreeBSD 3 and later use GNU C++ and GNU ld with standard ELF
     # conventions
     ld_shlibs=yes
@@ -404,7 +404,7 @@ case $host_os in
         ;;
     esac
     ;;
-  netbsd*)
+  netbsd* | knetbsd*-gnu)
     # NetBSD uses g++ - do we need to do anything?
     ;;
   osf3*)
@@ -759,7 +759,7 @@ else
           ;;
       esac
       ;;
-    freebsd*)
+    freebsd* | kfreebsd*-gnu)
       # FreeBSD uses GNU C++
       ;;
     gnu*)