x11-toolkits/wlroots: limit hwdata dependency to DRM as build only

pnp.ids is converted to pnpids.c, so won't pick up changes without rebuild.
pnp.ids is also unused when nesting on X11 or Wayland (WLR_BACKENDS != drm).
https://gitlab.freedesktop.org/wlroots/wlroots/-/commit/eec95e3d5e1a

(cherry picked from commit 146bb4da8d31a34f013b593b85f47796cd06158d)