libweston: Move 'struct weston_backend' to the internal backend header

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
2 jobs for libweston-split in 1 minute and 27 seconds (queued for 9 seconds)
latest
Status Job ID Name Coverage
  Container Prep
passed #429922
container_prep

00:00:24

 
  Build
passed #429924
build-native-meson

00:01:03