package/weston: bump to version 8.0.0

package/weston: bump to version 8.0.0

The autotools build system is deprecated and replaced with meson for weston.

We need to enable pango when building demo clients since it is required
by meson.

The dbus option in autotools is replaced with launcher-logind in meson
which is only ever used with systemd, so add it to the condition.

Replaced WESTON_NATIVE_BACKEND with backend-default in meson.

Added systemd dependency as launcher-logind depends on both dbus
and systemd and is the only dependency that requires dbus.

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Tested-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>