libidn: Removal of package as no longer needed.

libidn: Removal of package as no longer needed.

- A while back elinks changed from using libidn to libidn2. At that time that left
   ghostscript as the only package still using libidn. With the removal of cups and
   associated packages, including ghostscript, libidn is no longer used. libidn2 is
   used where required now.
- This removes the lfs and rootfiles and removes the entry from the make.sh file.

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>