Enable xapp_bdftopcf dependencies for the host

Now that xapp_bdftopcf is enabled on the host, we also need its
dependencies to be available for the host. The dependency of
host-xapp_bdftopcf is host-xlib_libXfont, which itself depends on a
bunch of other packages. Some of them were already available for the
host, some not (xfont_encodings, xlib_xtrans, xproto_fontcacheproto,
xproto_fontsproto) and are therefore added by this patch.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>