drm/arm: Make ARM devices menu depend on DRM

Otherwise if CONFIG_DRM is disabled, menuconfig will show an empty menu.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230703230534.997525-4-javierm@redhat.com