lcdproc: fix autobuilder failures

The lcdproc version bump to 0.5.6 has resulted in autobuilder failures such as
the following.

  http://autobuild.buildroot.org/results/9967bc20a6094e836c4c18ff2cd30edef143bb8e/build-end.log



The 0.5.6 release added a new glcd driver, which requires the freetype and zlib
libraries. This patch makes the lcdproc package depend on freetype and zlib.

Signed-off-by: Simon Dawson <spdawson@gmail.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>