drm: Include <drm/drm_device.h>

Include <drm/drm_device.h> in drm_ioc32.c. Resolves a depenency
on <drm/drm_legacy.h>, which will be removed.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: David Airlie <airlied@gmail.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20231122122449.11588-7-tzimmermann@suse.de