MAINTAINERS: add Danilo Krummrich as Rust reviewer

Danilo has been involved with the Rust for Linux project for a year now.
He is primarily working on the Nova GPU driver [1][2].

In addition, he has been active in the mailing list and most recently
submitted the Device / Driver PCI / Platform series.

He is also already a maintainer of `RUST [ALLOC]` as well as several
other DRM-related entries.

His expertise developing Rust abstractions and APIs for one of the major
users of Rust in the kernel will be very useful to have around in the
future. Thus add him to the `RUST` entry as reviewer.

Link: https://rust-for-linux.com/nova-gpu-driver [1]
Link: https://lore.kernel.org/dri-devel/Zfsj0_tb-0-tNrJy@cassiopeiae/ [2]
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Acked-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250129215948.135486-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>