ANDROID: rust: mm: add bindings for memory management

Add abstraction for working with the memory management types mm_struct
and vm_area_struct. This patch will be a follow-up to the memory
management patchset [1] (or included in a future version thereof).

This patch is an improved version of a patch included in the list of
dependencies of the Rust Binder RFC [2]. It is marked ANDROID: because
it has not yet been sent to the mailing list. It's mostly ready, but I
want to go through it one more time before I send it.

Link: https://lore.kernel.org/all/20240124-alice-mm-v1-0-d1abcec83c44@google.com/ [1]
Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-0-08ba9197f637@google.com/

 [2]
Bug: 324206405
Co-developed-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Change-Id: I8d0c71fcf76027ccc08ef83f36b51da4665125d9
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>