MAINTAINERS: add miscdevice Rust abstractions

Add rust abstractions to miscdevice MAINTAINERS entry.

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250705-miscdevice-maintainers-v1-1-9a6b67f7602f@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: tamird

MAINTAINERS

@@ -5568,6 +5568,7 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
 F:	drivers/char/
 F:	drivers/misc/
 F:	include/linux/miscdevice.h
+F:	rust/kernel/miscdevice.rs
 F:	samples/rust/rust_misc_device.rs
 X:	drivers/char/agp/
 X:	drivers/char/hw_random/