rust: macros: use quote! for module! macro

This has no behavioural change, but is good for maintainability. With
`quote!`, we're no longer using string templates, so we don't need to
quote " and {} inside the template anymore. Further more, editors can
now highlight the code template.

This also improves the robustness as it eliminates the need for string
quoting and escaping.

Co-developed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Gary Guo <gary@garyguo.net>

Author: nbdd0121