complibs: remove experimental from versions selection

Since I removed EXPERIMENTAL to most of gcc versions, the configuration
is now broken, as the required companion libraries versions are not
selectable, as they are still hidden behind EXPERIMENTAL.

Reported-by: Claudio Henrique Fortes Felix (chffelix on irc://irc.freenode.net/crosstool-ng)
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

 # This file adds functions to build the C library for bare metal (IE. none)

 # Copyright 2008 Yann E. MORIN

 # Licensed under the GPL v2. See COPYING in the root of this package

 do_libc_get() {

     :

 }

 do_libc_extract() {

     :

 }

 do_libc_check_config() {

     :

 }

 do_libc_start_files() {

     :

 }

 do_libc() {

     :

 }

 do_libc_finish() {

     :

 }