MAINTAINERS: add DRM Rust source files to DRM DRIVERS
Add the DRM Rust source files to the DRM DRIVERS maintainers entry.
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-9-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>