perl-Imager: Removal of all tiff related lines in rootfile

perl-Imager: Removal of all tiff related lines in rootfile

- With removal of libtiff, the perl-Imager rootfile has to have tiff related lines
   removed.
- perl-Imager works without the tiff lines in place. Only no tiff images will be able
   to be processed by perl-Imager but that is not required for its use in IPFire.
- Tested out creating an OpenVPN connection with OTP enabled and the OTP QR code was
   produced and able to be viewed.

Tested-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>