MAINTAINERS: mailmap: update Benno Lossin's email address

Update Benno Lossin's email address to `@kernel.org`.

Signed-off-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250519143952.11412-1-lossin@kernel.org


[ Fixed email in `.mailmap`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>