compositor: Drop legacy backends in favor of libinput

Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
diff --git a/src/compositor-drm.c b/src/compositor-drm.c
index 702bae8..a5b6eb7 100644
--- a/src/compositor-drm.c
+++ b/src/compositor-drm.c
@@ -47,7 +47,7 @@
 #include "compositor.h"
 #include "gl-renderer.h"
 #include "pixman-renderer.h"
-#include "udev-input.h"
+#include "libinput-seat.h"
 #include "launcher-util.h"
 #include "vaapi-recorder.h"